BATRACHIA  . The arguments adduced by T . H . See also:

• HUXLEY, THOMAS HENRY (1825–1895)

Huxley, in his See also:

• ARTICLE (from Lat. articulus, a joint)

article on this subject in the ninth edition of the Ency 1opaedia Britannia', for applying the name See also:

• AMPHIBIA

Amphibia to those See also:

• LUNG

lung-breathing, pentadactyle vertebrates which had been first severed from the Linnaean Amphibia by See also:

• ALEXANDRE, NOEL (NATALIS ALEXANDER) (1639-1724)

Alexandre See also:

• BRONGNIART, ADOLPHE THEODORE (1801–1876)
• BRONGNIART, ALEXANDRE (1770-1847)

Brongniart, under the name of Batrachia, have not met with universal See also:

• ACCEPTANCE (Lat. acceptare, frequentative form of accipere, to receive)

acceptance . Although much used in See also:

• TEXT (Lat. textum, woven fabric, from texere, to weave)

text-books and anatomical See also:

• WORKS

works in See also:

• GREAT

Great See also:

• BRITAIN (Gr. Hperavuml vi7vot, Bperravia; Lat. Britannia, rarely Britannia)

Britain and in See also:

• GERMANY
• GERMANY (Ger. Deutschland)

Germany, the former name has been discarded; in favour of the latter by the See also:

• PRINCIPAL

principal authors on systematic herpetology, such as W . See also:

• PETERS (or PETER), HUGH (1598–166o)
• PETERS, KARL (1856– )

Peters, A . See also:

• GUNTHER, JOHANN CHRISTIAN (1695-1723)

Gunther and E . D . See also:

• COPE
• COPE (M.E. cape, cope, from Med. Lat. capa, cappa)
• COPE, EDWARD DRINKER (1840-1897)
• COPE, EDWARD MEREDITH (1818-1873)

Cope, and their See also:

• LEAD
• LEAD (pronounced iced)

lead is followed in the See also:

• PRESENT

present article . Bearing in mind that See also:

• LINNAEUS

Linnaeus, in his use of the name Amphibia, was not alluding to the gill-breathing and See also:

• AIR (from an Indo-European root meaning " breathe," " blow ")
• AIR, or ASBEN

air-breathing periods through which most frogs and newts pass in the course of their existence, but only wished to convey the fact that many of the constituents of the See also:

• GROUP

group resort to both See also:

• LAND

land and See also:

• WATER

water (e.g. crocodiles), it seems hard to admit that the See also:

• TERM

term may be thus diverted from its See also:

• ORIGINAL

original signification, especially when such a See also:

• CHANGE (derived through the Fr. from the Late Lat. cambium, cambiare, to barter; the ultimate derivation is probably from the root which appears in the Gr. «a urmu', to bend)

change results in discarding the name expressly proposed by Brongniart to denote' the association which has ever since been universally adopted either as an See also:

• ORDER
• ORDER (through Fr. ordre, for earlier ordene, from Lat. ordo, ordinis, rank, service, arrangement; the ultimate source is generally taken to be the root seen in Lat. oriri, rise, arise, begin; cf. " origin ")
• ORDER, HOLY

order, a sub-class or a class . Many authors who have devoted See also:

• SPECIAL

special See also:

• ATTENTION (from Lat. ad-tendo, await, expect; the condition of being " stretched " or " tense ")

attention to questions of nomenclature therefore think Reptilia and Batrachia the correct names of the two great classes into which the Linnaean Amphibia have been divided, and consider that the latter term should be reserved for the use of those who, like that great authority, the See also:

• LATE

late See also:

• PROFESSOR (the Latin noun formed from the verb profiteri, to declare publicly, to acknowledge, profess)

Professor Peters, down to the See also:

• TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
• TIME, MEASUREMENT OF
• TIME, STANDARD

time of his See also:

• DEATH

death in 1883, would persist in regarding See also:

• REPTILES (Lat. Reptilia, creeping things, from reptilis; ref ere, to creep; Gr. Ep7rety, whence the term " herpetology," for the science dealing with them)

reptiles and batrachians as See also:

• MERE
• MERE, ADALBERT (1838-1909)

mere sub-classes (1) . However extraordinary it may appear, especially to those who bring the living forms only into See also:

• FOCUS (Latin for " hearth " or " fireplace ")

focus, that opposition should still be made to Huxley's See also:

• PRIMARY

primary See also:

• DIVISION (from Lat. dividere, to break up into parts, separate)

division of the vertebrates other than mammals into See also:

• SAUROPSIDA

Sauropsida (birds and reptiles) and Ichthyopsida (batrachians and fishes), it is certain that See also:

• RECENT

recent discoveries in palaeontology have reduced the See also:

• GAP

gap between batrachians and reptiles to such a minimum as to cause the greatest embarrassment in the See also:

• ATTEMPT (Lat. adtemptare, attentare, to try)

attempt to draw a satisfactory See also:

• LINE

line of separation between the two; on the other See also:

• HAND
• HAND (a word common to Teutonic languages; cf. Ger. Hand, Goth. handus)
• HAND, FERDINAND GOTTHELF (1786-185r)

hand the See also:

• HIATUS (Lat. for gaping, or gap)

hiatus between fishes and batrachians remains as wide as it was at the time Huxley's article Amphibia (See also:

• ENCYCLOPAEDIA

Encyclopaedia Britannica, 9th ed.) was written .

The See also:

• CHIEF (from Fr. chef, head, Lat. caput)

chief See also:

• CHARACTER (Gr. xapareri7p, from xap&crew, to scratch)

character which distinguishes the Batrachians from the reptiles, leaving aside the metamorphoses, lies in the arrangement of the bones of the See also:

• PALATE (Lat. palatum, possibly from the root of pascere, to feed)

palate, where a large parasphenoid extends forwards as far or nearly as far as the vomers and widely separates the pterygoids . The bones which See also:

• BEAR
• BEAR, BLACK
• BEAR, BROWN
• BEAR, GRIZZLY
• BEAR, ISABELLINE
• BEAR, WHITE

bear the two occipital condyles have given rise to much discussion, and the See also:

• DEFINITION (Lat. definitio, from de-finire, to set limits to, describe)

definition given by Huxley in the previous edition—" two occipital condyles, the basi-occipital region of the See also:

• SKULL

skull either very incompletely or not at all ossified "—requires revision . Some authors have held that the See also:

• BONE (a word common in various forms to Teutonic languages, in many of which it is confined to the shank of the leg, as in the German Bein)
• BONE, HENRY (1755-1834)

bone on which the occipital condyles have been found most See also:

• DEVELOPED

developed in some labyrinthodonts (2) represents a large basi-occipital bearing two knobs for the See also:

• ARTICULATION (from Lat. articulare, to divide into joints)

articulation with the first vertebra, whilst the skull of the batrachians of the present See also:

• DAY (O. Eng. dreg, Ger. Tag; according to the New English Dictionary, " in no way related to the Lat. dies")
• DAY, JOHN (1574-1640?)
• DAY, THOMAS (1748-1789)

day has lost the basi-occipital, and the condyles are furnished by the exoccipitals . On the other hand, some reptiles have the occipital condyle divided into two and produced either by the basi-occipital or by the ex-occipitals . But the recent find of a well preserved skull of a labyrinthodont (Capitosaurus stantonensis) from the Trias of See also:

• STAFFORDSHIRE

Staffordshire has enabled A . S . See also:

• WOODWARD, JOHN
• WOODWARD, SAMUEL (179o-1838)

Woodward (3) to show that, in that See also:

• FORM (Lat. forma)

form at any See also:

• RATE

rate, the condyles are really exoccipital, although they are separated by a narrow basi-occipital . It is therefore very probable that the authors quoted in (2) were mistaken in their See also:

• IDENTIFICATION (Lat. idem, the same)

identification of the elements at' the See also:

• BASE

base of the foramen magnum . The fact remains, however, that some if not all of the stegocephalous batrachians have an ossified basi-occipital . As a result of his researches on the anomodont reptiles and the Stegocephalia (4), as the See also:

• EXTINCT

extinct order that includes the well known labyrinthodonts is now called, we have had the proposal by H . G . See also:

• SEELEY
• SEELEY, SIR JOHN ROBERT (1834–1895)

Seeley (5) to See also:

• PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)

place the latter with the reptiles instead of with the batrachians, and H .

Gadow, in his most recent See also:

• CLASSIFICATION (Lat. classis, a class, probably from the root cal-, cla-, as in Gr. icaMce, clamor)

classification (6), places some of them among the reptiles, others being See also:

• LEFT

left with the batrachians; whilst H . See also:

• CREDNER, CARL FRIEDRICH HEINRICH (1809-1876)

Credner, basing his views on the See also:

• DISCOVERY

discovery by him of various annectent forms between the Stegocephalia and the Rhynchocephalian reptiles, has proposed a class, Eotetrapoda, to include these forms, ancestors of the batrachians proper on the one hand, of the reptiles proper on the other . Yet, that the Stegocephalia, notwithstanding their great See also:

• AFFINITY (Lat. affinitas, relationship by marriage, from offinis, bordering on, related to; finis, border, boundary)
• AFFINITY, CHEMICAL

affinity to the reptiles, ought to be included in the batrachians as commonly understood, seems sufficiently obvious from the mere fact of their passing through a branchiate See also:

• CONDITION (Lat. condicio, from condicere, to agree upon, arrange; not connected with conditio, from condere, conditum, to put together)

condition, i.e. undergoing See also:

• METAMORPHOSIS

metamorphosis (7) . The outcome of our present knowledge points to the Stegocephalia, probably themselves derived from the Crossopterygian fishes (8), having yielded on the one hand the true batrachians (retrogressive See also:

• SERIES (a Latin word from serere, to join)

series), with which they are to a certain extent connected through the Caudata and the Apoda, on the other hand the reptiles (progressive series), through the Rhynchocephalians and the Anomodonts, the latter being believed, on very suggestive See also:

• EVIDENCE (Lat. evidentia, evideri, to appear clearly)

evidence, to lead to the mammals (9) . The division of the class Amphibia or Batrachia into four orders, as carried out by Huxley, is maintained, with, however, a change of names: Stegocephalia, for the assemblage of See also:

• MINOR
• MINOR (Lat. for smaller, lesser)
• MINOR, ROBERT CRANNELL (1839-1904)

minor See also:

• GROUPS
• GROUPS, THEORY

groups that cluster See also:

• ROUND (O. Fr. rond, Lat. rotundus, the Fr. is the source also of Du. rond; Ger., Swed., Dan. and Nor. rond)

round the Labyrinthodonta of R . See also:

• OWEN, JOHN (1616-1683)
• OWEN, JOHN [OVENUS Or AUDOENUS] (c. 1560-1622)
• OWEN, ROBERT (1771-1858)
• OWEN, SIR HUGH (1804-1881)
• OWEN, SIR RICHARD (1804–1892)

Owen, which name is restricted to the forms for which it was originally in-tended; Peromela, Urodela, Anura, are changed to A poda, Caudata, Ecaudata, for the See also:

• REASON (Lat. ratio, through French raison)

reason that (unless obviously misleading, which is not the See also:

• CASE
• CASE, JOHN (d. 1600)

case in the present instance) the first proposed name should supersede all others for higher groups as well as for genera and See also:

• SPECIES

species, and the latter set have the benefit of the See also:

• LAW
• LAW (0. Eng. lagu, M. Eng. lawe; from an old Teutonic root lag, " lie," what lies fixed or evenly; cf. Lat. lex, Fr. loi)
• LAW, JOHN (1671—1729)
• LAW, WILLIAM (1686-1761)

law of priority . In the first subdivision of the batrachians into two families by C . Dumeril in 1806 (Zool . Anal. pp . 90-94) these are termed " Anoures " and FIo . 1.- Upper view of Archego-" Urodeles in See also:

• FRENCH
• FRENCH, DANIEL CHESTER (1850– )
• FRENCH, NICHOLAS (1604-1678)

French, saurus Decheni . (Outlines and Caudati in pm, Praema maxill after st, Sup St p ratem-Latin .

When Dumeril's n, Nasal. poral . See also:

• PUPIL (Lat. pupillus, orphan, minor, dim. of pupus, boy, allied to puer, from root pm- or peu-, to beget, cf. "pupa," Lat. for " doll," the name given to the stage intervening between the larval and imaginal stages in certain insects)

pupil, M . See also:

• OPPEL, CARL ALBERT (1831–1865)

Oppel, in 1811 m, Maxilla. sq, Squamosal . (Ordn . Rept . P . 72), added 1, Lachrymal. pto, Postorbital . the Caecilians, he named pf, Praefrontal. qi, Quadrato- the three A oda j, See also:

• J1(P)
• J1(Z)

J1. fupt groups p j, Jugal. uga o, Occipital . Ecaudata and Caudata . The ptf, Postfrontal. pt, See also:

• POST

Post-See also:

• TERN (Norsk taerne, tende or tende; Swedish tarna; Dutch Stern1)

tern- Latin form being the only P, Parietal. poral . one entitled to recognition 4 . Quadrate .

in zoological nomenclature, it follows that the last-mentioned names should be adopted for the three orders into which recent batrachians are divided . 1 . STEGOCEPHALIA (1Q).—Tailed, lacertiform or serpentiform batrachians, with the temporal region of the skull roofed over by postorbital, squamosal, and supratemporal plates similar to the same bones in Crossopterygian fishes, and likewise with paired dermal bones (occipitals and post-temporals) behind the parietals and supratemporals . A parietal foramen; scales or bony scutes frequently present, especially on the ventral region, which is further protected by three large bony plates—interclavicle and clavicles. the latter in addition to cleithra . Extinct, ranging from the Upper Devonian to the Trias . Our knowledge of Devonian forms is still extremely meagre, the only certain See also:

• PROOF (in M. Eng. preove, proeve, preve, &°c., from O. Fr . prueve, proeve, &c., mod. preuve, Late. Lat. proba, probate, to prove, to test the goodness of anything, probus, good)

proof of the existence of pentadactyle vertebrates at that See also:

• PERIOD
• PERIOD (Gr. irepioSos, a going or way round, circuit, aepi, round, and &Sis, way, road)

period resting on the footprints discovered in See also:

• PENNSYLVANIA
• PENNSYLVANIA, UNIVERSITY OF

Pennsylvania and described by O . C . See also:

• MARSH (O. F. mersc, for merisc, a place full of "meres" or pools; cf. Ger. Meer, sea, Lat. mare)
• MARSH, ADAM (ADAM DE MARISCO) (d. c. 1258)
• MARSH, GEORGE PERKINS (1801-1882)
• MARSH, HERBERT (1757–1839)
• MARSH, NARCISSUS (1638-1713)
• MARSH, OTHNIEL CHARLES (1831-1899)

Marsh (11) as Tinopus antiquus . Sundry remains from See also:

• BELGIUM
• BELGIUM (Fr. Belgique; Flem. Belgic)

Belgium, as to the identification of which doubts are still entertained, have been regarded by M . Lohest (12) as evidence of these batrachians in the Devonian . Over zoo species are now distinguished, from the Carboniferous of See also:

• EUROPE

Europe and See also:

• NORTH
• NORTH, BARONS
• NORTH, MARIANNE (1830—1890)
• NORTH, ROGER (1653-1734)
• NORTH, SIR THOMAS (1535?-16o1?)

North See also:

• AMERICA

America, the See also:

• PERMIAN

Permian of See also:

• SPITSBERGEN (the name being Dutch is incorrectly, though commonly, spelled Spitzbergen)

Spitsbergen, Europe, North America and See also:

• SOUTH
• SOUTH, ROBERT (1634–1716)

South See also:

• AFRICA
• AFRICA, ROMAN

Africa, and the Trias of Europe, America, South Africa, See also:

• INDIA
• INDIA, FRENCH

India and See also:

• AUSTRALIA

Australia . The forms of batrachians with which we are acquainted show the vertebral See also:

• COLUMN (Lat. columna)

column to have been evolved in the course of time from a notochordal condition with segmented centra similar to that of See also:

• EARLY
• EARLY, JUBAL ANDERSON (1816-1894)

early bony ganoid fishes (e.g .

Caturus, Eurycormus), to biconcave contra, and finally to the socket-and-See also:

• HALL
• HALL (generally known as SCHWABISCH-HALL, tc distinguish it from the small town of Hall in Tirol and Bad-Hall, a health resort in Upper Austria)
• HALL (O.E. heall, a common Teutonic word, cf. Ger. Halle)
• HALL, BASIL (1788-1844)
• HALL, CARL CHRISTIAN (1812–1888)
• HALL, CHARLES FRANCIS (1821-1871)
• HALL, CHRISTOPHER NEWMAN (1816—19oz)
• HALL, EDWARD (c. 1498-1547)
• HALL, FITZEDWARD (1825-1901)
• HALL, ISAAC HOLLISTER (1837-1896)
• HALL, JAMES (1793–1868)
• HALL, JAMES (1811–1898)
• HALL, JOSEPH (1574-1656)
• HALL, MARSHALL (1790-1857)
• HALL, ROBERT (1764-1831)
• HALL, SAMUEL CARTER (5800-5889)
• HALL, SIR JAMES (1761-1832)
• HALL, WILLIAM EDWARD (1835-1894)

hall condition that prevails at the present day . However, owing to the See also:

• EVOLUTION

evolution of the vertebral column in various directions, and to the inconstant See also:

• STATE
• STATE, GREAT OFFICERS OF

state of things in certain annectent groups, it is not possible, it seems, to apply the vertebral characters to taxonomy with that rigidity which E . D . Cope and some other recent authors have attempted to enforce . This is particularly evident in the case of the Stegocephalians; and recent batrachians, tailed and tailless, show the mode of articulation of the vertebrae,whether amphicoelous, opisthocoelous or procoelous, to he of but secondary systematic importance in dealing with these lowly vertebrates . The following division of the Stegocephalians into five sub-orders is therefore open to serious See also:

• CRITICISM
• CRITICISM (from the Gr. KpiTrlS, a judge, Kpivew, to decide, to give an authoritative opinion)

criticism; but it seems on the whole the most natural to adopt in the See also:

• LIGHT

light of our present knowledge . A . Rhachitomi, (See also:

• FIGS

figs . I, 2), in which the See also:

• SPINAL

spinal See also:

• CORD (derived through the Fr. corde, from the Lat. chorda, Gr. xop(5rt, the string of a musical instrument)

cord rests on the notochord, which persists uninterrupted and is surrounded by three bony elements in addition to the neural See also:

• ARCH
• ARCH, JOSEPH (1826– )

arch a so-called pleurocentrum on each See also:

• SIDE
• SIDE (mod. Eski Adalia)

side, which appears to represent the centrum proper of reptiles and mammals, and an intercentrum or hypocentrum below, which may extend to the neural arch, and probably answers to the hypapophysis, as it is produced into chevrons in the caudal region . Mostly large forms, of Carboniferous and Permian See also:

• AGE (Fr. age, through late Lat. aetaticum, from aetas)

age, with a more or less complex infolding of the walls of the See also:

• TEETH (O.E. Eel); plural of tooth, O.E. top)

teeth . Families: ARCHEGOSAURIDAE, ERYOPIDAE, TRIMERORHACHIDAE, DISSORHOPHIDAE . The last is remarkable for an extraordinary endo- and exo-skeletal See also:

• CARAPACE (a Fr. word, from the Span. carapacho, a shield or armour)

carapace, Dissorhophus being described by Cope (13) as a " batrachian See also:

• ARMADILLO

armadillo." B .

Embolomeri, with the centra and intercentra equally developed disks, of which there are thus two to each neural arch; these disks perforated in the See also:

• MIDDLE

middle for the passage of the notochord . This type may be directly derived from the preceding, with which it appears to be connected by the genus Diplospondylus . Fam.: CRICOTIDAE, Permian . C . Labyrinthodonta, with See also:

• SIMPLE

simple biconcave vertebral disks, very slightly pierced by a remnant of the notochord and supporting the loosely articulated neural arch . .`' This condition is derived from (Outline after Jaekel.) that of the Rhachitomi, as shown by the structure of the vertebral column in See also:

• YOUNG
• YOUNG, A
• YOUNG, ARTHUR (1741-1820)
• YOUNG, BRIGHAM (1801-1877)
• YOUNG, CHARLES MAYNE (1777–1856)
• YOUNG, EDWARD (1683–1765)
• YOUNG, JAMES (1811-1883)
• YOUNG, THOMAS (1773-1829)

young specimens . Mostly large forms from the Trias (a few Permian), with true labyrinthic dentition . Families: LABY RINTHODONTIDAE, ANTHRACOSAURIDAE, DENDRERPETIDAE, NY RANIIDAE . D . Microsauria, nearest the reptiles, with persistent notochord completely surrounded by constricted cylinders on which the neural arch rests . Teeth hollow, with simple or only slightly folded walls . Mostly of small See also:

• SIZE

size and abundant in the Carboniferous and See also:

• LOWER

Lower Permian .

Families: UROCORDYLIDAE, LIMNERPETIDAE, HYLONOMIDAE (fig . 3), MICROBRACHIDAE, DOLICHOSOMATIDAE; the latter serpentiform, apodal . E . Branchiosauria, nearest to the true batrachians; with persistent non-constricted notochord, surrounded by See also:

• BARREL (a word of uncertain origin common to Romance languages; the Celtic forms, as in the Gaelic baraill, are derived from the English)

barrel-shaped, bony cylinders formed by the neural arch above and a pair of intercentra below, both these elements taking an equal See also:

• SHARE (O. Eng. scearu, chiefly in compounds, e.g. land-scearu, a share of land, from sceran to cut; cf. " shear" )

share in the formation of a transverse See also:

• PROCESS

process on each side for the support of the See also:

• RIB (from 0. Eng. ribb; the word appears' in many Teutonic languages, cf. Ger. Rippe, Swed. reb)

rib . This See also:

• PLAN
• PLAN (from Lat. planes, flat)

plan of structure, apparently evolved out of the rhachitomous type by suppression of the pleurocentra and the downward See also:

• EXTENSION (Lat. ex, out ; tendere, to stretch)

extension of the neural arch, leads to that characteristic of frogs in which, as development shows, the vertebra is formed wholly or for the greater See also:

• PART

part by the neural arch (14) . Small forms from the Upper Carboniferous and Permian formations . A single See also:

• FAMILY

family: BRANCHIOSAURIDAE . II . APODA (15).—No limbs . Tail vestigial or absent . 'Frontal bones distinct from parietals; palatines fused with maxillaries . Male with an intromittent copulatory, See also:

• ORGAN

organ .

Degraded, See also:

• WORM

worm-like batrachians of still obscure See also:

• AFFINITIES

affinities, inhabiting tropical Africa, south-eastern See also:

• ASIA

Asia and tropical America . See also:

• THIRTY

Thirty-three species are known . No fossils have yet been discovered . It has been attempted Af late to do away .with this order altogether and to make the Caecilians merely a family of the Urodeles . This view has originatedout of the very remarkable superficial resemblance between the Ichthyophis-larva and the Amphiuma . Cope (16) regarded the Apoda as the extremes of a line of degeneration from the Salamanders, with Amphiuma as one of the annectent forms . In the See also:

• OPINION (Lat. opinio, from opinari, to think)

opinion of P. and F . See also:

• SARASIN, or SARRAZIN, JEAN FRANCOIS (1611?-1654)

Sarasin (17), whose great See also:

• WORK

work on the development of Ichthyophis is one of the See also:

• MOAT

moat important recent contributions to our knowledge of the batrachians, Amphiuma is a sort of neotenic Caecilian, a larval form become sexually mature while retaining the branchial respiration . If the See also:

• ABSENCE (Lat. absentia)

absence of limbs and the reduction of the tail were the only characteristic of the group, there would be, of course, no objection to unite the Caecilians with the Urodeles; but, to say nothing of the scales, present in many genera of Apodals and absent in all Caudates, which have been shown by H . Credner to be identical in structure with FIG . 3.—A, Dorsal vertebra of Hytonothose of Stegocephalians, the Caecilian skull pre- See also:

• MUS

mus (side view and front view) . B, Dorsal Bents features which are vertebra of Branchiosaurus (side view and not shared by any of front view). n, Neural See also:

• CANAL
• CANAL (from Lat. canalis, " channel " and " kennel " being doublets of the word)

canal; ch, chorda. the tailed batrachians .

(After Credner.) G . M . See also:

• WINSLOW, EDWARD (1595-1655)

Winslow (18), who has made a study of the chondrocranium of Ichthyophis, concludes that its condition could not have been derived from a Urodele form, but points to some more See also:

• PRIMITIVE

primitive ancestor . That this ancestor was nearly related to, if not one of, the Stegocephalians, future discovery will in all See also:

• PROBABILITY (Lat. probabilis, probable or credible)

probability show . A B North America . This order contains about 150 species, referred to five families: HYLAEOBATRACHIDAE, SALAMANDRIDAE, AMPHIUMIDAE, PROTEIDAE, SIRENIDAE . Fossil remains are few in the Upper See also:

• EOCENE (Gr. *In, dawn, icauvos, recent)

Eocene and See also:

• MIOCENE

Miocene of Europe and the Upper Cretaceous of North America . The See also:

• OLDEST

oldest Urodele known is Hylaeobalrachus Dollo (21) from the Lower Wealdenof Belgium . At present this order is confined to the See also:

• NORTHERN

northern hemisphere, with the exception of two Spelerpes from the See also:

• ANDES

Andes of See also:

• ECUADOR (officially La Republica del Ecuador)

Ecuador and See also:

• PERU
• PERU (apparently from Biru, a small river on the west coast of Colombia, where Pizarro landed)

Peru, and a Plethodon from See also:

• ARGENTINA

Argentina . IV . ECAUDATA (22).—Frogs and toads . Four limbs and no tail .

See also:

• RADIUS

Radius confluent with ulna, and See also:

• TIBIA

tibia with fibula; See also:

• TARSUS (mod. Tersous)

tarsus (astragalus and calcaneum) elongate, forming an additional segment in the See also:

• HIND

hind See also:

• LIMB

limb . Caudal vertebrae fused into a urostyle or coccyx . Frontal bones confluent with parietals . This order embraces about 1300 species, of which some 40 are fossil, divided into two sub-orders and sixteen families: A . Aglossa,—Eustachian tubes See also:

• UNITED

united into a single ostium pharyngeum; no See also:

• TONGUE (O. Eng. lunge)

tongue . DACTYLETH RIDAE, PIPIDAE . B . Phaneroglossa,—Eustachian tubes separated; tongue present . DISCOGLOSSIDAE,PELOBATIDAE, HEMIPHRACTIDAE,AMPHIGNATHODONTIDAE, HYLIDAE, BUFONIDAE, DENDROPHRYNISCIDAE, CYSTIGNATHIDAE, DYSCOPHIDAE,GENYOPHRYNIDAE,ENGYSTOMATIDAE, CERATOBATRACHIDAE, RANIDAE, DENDROBATIDAE . The Phaneroglossa are divided into two groups; Arcifera and Firmisternia, representing two stages of evolution . The family characters are mainly derived from the See also:

• DILATATION (from Lat. dis-, distributive, and lotus, wide)

dilatation or non-dilatation of the sacral diapophyses, and the presence of teeth in one or both jaws, or their absence . The Discoglossidae are noteworthy for the presence of See also:

• SHORT, FRANCIS JOB (1857– )

short ribs to some of the vertebrae, and in some other points also they approach the tailed batrachians; they may be safely regarded as, on the whole, the most generalized of known Ecaudata .

Distinct ribs are present at an early age in the Aglossa, as discovered by W . G . Ridewood (23) . The recent addition of a third genus of Aglossa, Hymenochirus (24) from tropical Africa, combining characters of Pipa and Xenopus, has removed every doubt as to the real affinity which connects these genera . Hymenochirus is further remarkable for the presence of only six distinct pieces in the vertebral column, which is thus the most abbreviated among all the See also:

• VERTEBRATA

vertebrata . Frogs and toads occur wherever See also:

• INSECT

insect See also:

• FOOD
• FOOD (like the verb " to feed," from a Teutonic root, whence O. Eng. foda; cf. " fodder "; connected with Gr. lrareicOae, to feed)

food is procurable, and their See also:

• DISTRIBUTION (Lat. distribuere, to deal out)

distribution is a See also:

• WORLD

world-wide one, with the exception of many islands . Thus New See also:

• CALEDONIA

Caledonia, which has a See also:

• RICH, BARNABE (c. 1540-1617)
• RICH, CLAUDIUS JAMES (1787-1821)
• RICH, JOHN (1692-1761)
• RICH, PENELOPE, LADY (c. 1562–1607)
• RICH, RICHARD, 1ST BARON RICH (1490?-1567)

rich and quite special See also:

• LIZARD (Lat. lacertal)

lizard-See also:

• FAUNA

fauna, has no batrachians of its own, although the Australian Hyla aurea has been introduced with success . New See also:

• ZEALAND (also SEALAND Or SEELAND; Danish Sjaelland)

Zealand possesses only one species (Liopelma hochstetteri), which appears to be rare and restricted to the North See also:

• ISLAND (O.E. ieg =isle, +land')

Island . The See also:

• FOREST

forest regions of See also:

• SOUTHERN

southern Asia, Africa and South America are particularly rich in species . According, to our present knowledge, the Ecaudata can be traced about as far back in time as the Caudata . An unmistakable batrachian of this order, refe-red by its describer to Palaeobatrachus, a determination which is only provisional, has been discovered in the Kimmeridgian of the Sierra del Montsech, See also:

• CATALONIA (Cataluna)

Catalonia (25), in a therefore somewhat older formation than the See also:

• WEALDEN

Wealden Caudata Hylaeobatrachus . Apart from a few unsatisfactory remains from the Eocene of See also:

• WYOMING

Wyoming, fossil tailless batrachians are otherwise only known from the Oligocene, Miocene and See also:

• PLIOCENE (from the Gr. sr?eiov, mere, and xatvbs, recent)

Pliocene of Europe and India .

These forms differ very little from those that live at the present day in the same part of the world, and some of the genera (Discoglossus, Bufo, Oxyglossus, Rana) arc even identical . Palaeobatrachus (26), of which a number of species represented by skeletons of the perfect form and of the See also:

• TADPOLE

tadpole have been described from Miocene beds in Germany, Bohemia and See also:

• FRANCE
• FRANCE, ANATOLE (1844– )

France, seems to be referable to the Pelobatidae ; this genus has been considered as possibly one of the Aglossa, but the absence of ribs in the larvae speaks against such an association . Numerous additions have been made to our knowledge of the development and See also:

• NURSING

nursing habits, which are extremely varied, some forms dispensing with or hurrying through the metamorphoses and hopping out of the See also:

• EGG (O.E. aeg, cf. Ger. Ei, Swed. aegg, and prob. Gr. u,ov, Lat. ovum)
• EGG, AUGUSTUS LEOPOLD (1816-1863)

egg in the perfect condition (27) . See also:

• SKELETON

Skeleton.—In the earliest forms of this order, the Stegocephalia, we meet with considerable variety in the constitution of the vertebrae, and these modifications have been used for their classification . All agree, however, in having each vertebra formed of at least two pieces, the suture between which persists throughout See also:

• LIFE

life . In this they differ from the three orders which have living representatives . Even the inferior See also:

• ARCHES, COURT OF

arches or chevrons of the tail of salamanders are continuously ossified with the centra . As a See also:

• MATTER

matter of fact, these vertebrae have no centra proper, that part which should correspond with the centrum being formed, as a study of the development has shown (H . Gadow, 14), by the See also:

• MEETING (from " to meet," to come together, assemble, 0. Eng. metals ; cf. Du. moeten, Swed. mota, Goth. gamotjan, &c., derivatives of the Teut. word for a meeting, seen in O. Eng. Wit, moot, an assembly of the people; cf. witanagemot)

meeting and subsequent See also:

• COMPLETE

complete co-ossification of the two chief dorsal and ventral pairs of elements (tail-vertebrae of Caudata), or entirely by the pair of dorsal elements . In the Ecaudata, the vertebrae of the See also:

• TRUNK (Fr. tronc, Lat. truncus, cut off, maimed)

trunk are formed on two different plans . In some the notochord remains for a See also:

• LONG, GEORGE (1800-1879)
• LONG, JOHN DAVIS (1838– )

long time exposed along the ventral See also:

• SURFACE

surface, and, owing to the absence of cartilaginous formation around it, disappears without ever becoming invested otherwise than by a thin elastic membrane; it can be easily stripped off below the vertebrae in larval specimens on the point of metamorphosing . This has been termed the epichordal type .

In others, which represent the perichordal type, the greater share of the formation of the whole vertebra falls to the (paired) dorsal See also:

• CARTILAGE (Lat. cartilage, gristle)

cartilage, but there is in addition a narrow ventral or hypo-chordal cartilage which fuses with the dorsal or becomes connected with it by calcified See also:

• TISSUE (Fr. tissu, tissue, participle of tisser, Lat. texere, to weave)

tissue; the notochord is thus completely surrounded by a thick sheath in tadpoles with imperfectly developed limbs . This mode of formation of both the arch and the greater part or whole of the so-called centrum from the same cartilage explains why there is never a neuro-central suture in these batrachians . During segmentation of the dorsal cartilages mentioned above, which send out the transverse processes of diapophyses, there appears between each two centra an intervertebral cartilage, out of which the articulating condyle of the centrum is formed, and becomes attached B either to the vertebra anterior (procoelous type) or posterior (opisthocoelous type) to it, if not remaining as an See also:

• INDEPENDENT

independent, inter-vertebral, ossified See also:

• SPHERE (Gr. vclsa?pa, a ball or globe)

sphere, as we sometimes find in specimens of Pelobatidae . In the Caudata and Apoda, cartilage often persists between the vertebrae; this cartilage may become imperfectly separated into a See also:

• CUP (in O.E. cuppe; generally taken to be from Late Lat. cuppa, a variant of Lat. cupa, a cask, cf. Gr. KuaeXXov)

cup-and-See also:

• BALL (in Mid. Eng. bal; the word is probably cognate with " bale," Teutonic in origin, cf. also Lat. falls, and Gr. 7raXXa)
• BALL, JOHN (1585-1640)
• BALL, JOHN (1818-1889)
• BALL, JOHN (d. 1381)
• BALL, SIR ALEXANDER JOHN, BART
• BALL, THOMAS (1819- )

ball portion, the cup belonging to the posterior end of the vertebra . In such cases the distinction between amphicoelous and opisthocoelous vertebrae rests merely on a question of ossi- A fication, and has occasionally given rise to misunderstandings in the use of these terms . Amphicoelous (bi-See also:

• CONCAVE

concave) vertebrae are found in the Apoda and in some of the Caudata; opisthocoelous (convexo-concave) vertebrae in the higher Caudata and in the lower Ecaudata; whilst the great See also:

• MAJORITY (Fr. majorite; Med. Lat. majoritas; Lat. major, greater)

majority of the Ecaudata have procoelous (concavo-See also:

• CONVEX

convex) vertebrae . All living batrachians, and some of the Stegocephalia, have trans-See also:

• VERSE (from Lat. versus, literally a line or furrow drawn by turning the plough, from vertere, and afterwards signifying an arrangement of syllables into feet)

verse processes on the vertebrae that succeed the See also:

• ATLAS

atlas (fig . 4), some of which, in the Cau- data, are divided into a dorsal and a ventral portion . Ribs are present in the lower Ecaudata (Discoglossidae and larval Aglossa), but they are never connected with a sternum . It is in fact doubtful whether the .so-called sternum of batrachians, in most cases a mere See also:

• PLATE

plate of cartilage, has been correctly identified as such . When limbs are present, one vertebra, rarely two (fig . 5) or three, are distinguished as sacral, giving See also:

• ATTACHMENT

attachment to the ilia .

In the Ecaudata, the form of the transverse processes of the sacral vertebra varies very consider-ably, and has afforded important characters to the systematist . In accordance with the saltatorial habits of the members of this order, the vertebrae, which number from 40 to 60 in the Caudata, to up-wards of 200 in the Apoda, have become reduced to to as the ducens nerves leave the skull. normal number, viz., eight praecaudal, one sacral and an elongate coccyx or urostyle, formed by coalescence of at least two vertebrae . In some genera this coccyx is fused with the ninth vertebra, and contributes to the sy.,, II B (best rp, The rhinal process . pnl, The praenasal processes . an, The alinasal processes, shown by the removal of part of the See also:

• FLOOR (from O. Eng. flor, a word common to many Teutonic languages, cf. Dutch vloer, and Ger. Flur, a field, in the feminine, and a floor, masculine)

floor of the left nasal chamber . AO., The antorbital process . pd, The pedicle of the suspensorium continued into cv, the ventral erns of the suspensorium . cd, Its dorsal crus . tt, The tegmen tympani . SE, The sphen-ethmoid . EO., The exoccipitals . Qu.J., The quadratojugal .

II . V . VI . Foramina by which the optic; trigeminal and portio dura, and ab- sacrum, whilst in a few others the number of segments is still further reduced by the co-ossification of one or two vertebrae preceding that corresponding to the normal sacral and by the See also:

• FUSION

fusion of the two first vertebrae; the extreme of reduction being found in pm, z,. rns . se' the genus Hymenochirus, the vertebral column of which is figured here (fig . 6.) As stated above in the definition of the order, the Stegocephalia have retained most of the See also:

• CRANIAL

cranial bones which are to be found in the Crossopterygian fishes, and it is worthy of See also:

• NOTE
• NOTE (Lat. nota, mark, sign, from noscere, to know)

note that the bones termed post-temporals may give attachment-to a further bone so prolonged backwards as to suggest the probability of the skull being connected with the See also:

• SHOULDER (in O.E. sculder, cognate with Ger. Schulter, Dutch schouder, Swed. skuldra, &c; the root is unknown)

shoulder-See also:

• GIRDLE (O. Eng. gyrdel, from gyrdan, to gird; cf. Ger. Gurtel, Dutch gordel, from giirten and gorden; "gird" and its doublet " girth " together with the other Teutonic cognates have been referred by some to the root ghar—to seize, enclose, seen in Gr. )(s

girdle, as in most teleostome fishes . This sup-position is supported by a specimen from the Lower Permian of See also:

• AUTUN

Autun, determined as Actinodon frossardi, acquired in 1902 by the See also:

• BRITISH

British Museum, which shows a bone, similar to the so-called "epiotic See also:

• CORNU, MARIE

cornu " of the microsaurians, Ceraterpeton and Scincosaurus, to have the relations of the supra-cleithrum of fishes, thus confirming a See also:

• SUGGESTION

suggestion made by C . W . See also:

• ANDREWS, JAMES PETTIT (c. 1737–1797)
• ANDREWS, THOMAS (1813–1885)

Andrews (28) . As in fishes also, the sensory canal See also:

• SYSTEM

system must have been highly developed on the skulls of many labyrmthodonts, and the impressions left by these canals have been utilized by morphologists for homologizing the various elements of the cranial roof with those of Crossopterygians . The pineal foramen, in the parietal bones, is as constantly present as it is absent in the other orders . Although not strictly forming part of the skull, allusion should be made here to the See also:

• RING (O.E. hring; a word common to Teutonic languages; and probably cognate with the Lat. circus, Gr. KtpKOS or KpLKOS, Skt'. chakra, wheel, circle, cf. also " harangue "); in art, a band of circular shape of varying sizes, made of any material and used f

ring of sclerotic plates which has been found in many of the Stegocephalia, and which is only found elsewhere in a few Crossopterygian fishes as well as in many reptiles and birds .

In the orders which are still represented at the present day, the bones of the skull are reduced in number and the " primordial skull," er chondrocranium (fig . 7), remains to a greater or less extent unossified, even in the adult . Huxley's figures of the skull of a caecilian (Ichlhyophis glutinosus), fig . 8, of a perennibranchiate urodele (Necturus maculosus = Menobranchus lateralis), fig . 9, and of a See also:

• FROG

frog (Rana esculenta), fig. to, are here given for comparison . The skull, in the Apoda, is remarkably solid and compact, and it possesses a postorbital or postfrontal bone (marked t in the figure) which does not exist in any of the other living batrachians . The squamosal bone is large and either in contact with the frontals and parietals or separated from them by a vacuity; the See also:

• ORBIT (from Lat. orbita, a track, orbis, a wheel)

orbit is some-times roofed over by bone . The presence, in some genera, of a second See also:

• ROW, JOHN (c. 1525—1580)

row of mandibular teeth seems to indicate the former existence of a splenial See also:

• ELEMENT (Lat. elementum)

element, such as exists in See also:

• SIREN

Siren among the Caudata and apparently in the labyrinthodonts . In the Caudata, the frontals remain likewise distinct from the parietals, whilst in the Ecaudata the two elements are fused into one, and in a few forms (Aglossa,, some Pelobalidae) the paired condition of these bones has disappeared in the adult . Prefrontal bones are present in the Salamandridae and Amphiumidae, but absent (or fused with the nasals) in the other Caudata and in the Ecaudata . In most of the former the palatines fuse with the vomers, whilst they remain distinct, unless entirely lost, in the latter . The vomer is single, or absent, in the Aglossa .

In the lower See also:

• JAW (Mid. Eng. jawe, jowe and geowe, O. Eng. cheowan, connected with " chaw " and " chew," and in form with " jowl ")

jaw of most of the Ecaudata the svmphysial cartilages ossify separately from the dentary bones, forming the so-called mento-meckelian bones; but these symphysial bones, so distinct in the frog, are less so in the Hylidae and Bufonidae, almost indistinguishable in the Pelobalidae and Discoglossidae, whilst in the Aglossa they do not exist any more than in the other orders of batrachians . No batrachian is known to possess an ossified azygous supra-occipital . Although there are four branchial arches in all the larval forms of the three orders, and throughout life in the Sirenidae, the perenni- A B . FIG . 9.—Lateral, dorsal and ventral views of the cranium of Necturus maculosus . See also:

• ILL

Ill the dorsal view, the bones are removed from the left See also:

• HALF

half of the skhh11; in the ventral view, the parasphenoid, palato-pterygoid, and vomers are given in outline . The letters have, for the most part, the same signification as before . seventh See also:

• NERVE (Lat. nervus, Gr. vevpov, a bowstring)

nerve. suspensorium . V';V2,V3, First, second and third q, Quadrate process . divisions of the trigeminal. o, Otic process . s.s.l, Stapedio-suspensorial liga- Na, 'Posterior See also:

• HARES

hares . ment .

Mck, Meckel's cartilage . h.s.l, Hyo-suspensorial See also:

• LIGAMENT (Lat. ligamentum, from ligare, to bind)

ligament . Gl . (fig. to), The position of the m.h.l, Mandibulo.hyoid Ligament. glottis . Bb', Bbl, Basilbranchials . branchiate Proteidae have only three (see fig . Is) . In the adult Apoda these arches and the hyoid fuse into three transverse, curved or angular bones (see fig . 13), the two posterior disconnected from the hyoid . In the Ecaudata, as shown by E . Gaupp (29) and by W . G .

Ridewood (30), the whole hyobranebialapparatus forms a cartilaginous continuum, and during metamgrphosis the branchialia disappear without a trace . The hyoid of the adult frog (fig . I2) P.S . 'Lh' .. C EO . P.a . so . PS Au consists of a plate of cartilage with two slender cornua, three processes on each side, and two long bony rods behind, termed the thyro-hyals, which embrace the larynx . In the Aglossa, which are remarkable for the large size and complexity of the larynx, the thyro-hyal bones are incorporated into the laryngeal apparatus, whilst the recently discovered Hymenochirus is further remarkable for the large size and ossification of the hyoidean cornua (ceratohyals), a feature which, though not uncommon among the salamanders, is unique among the Ecaudata (31) . The See also:

• PECTORAL

pectoral girdle of the Stegocephalia is, of course, only known from the ossified ele- ments, the identifica- tion of which has given rise to some diversity of opinion . But C . See also:

• GEGENBAUR, CARL (1826-1903)

Gegenbaur's (32) inter- pretation may be re- garded as final .

He as shown that, as in the Crossopterygian and . Chondrostean ganoid fishes, there di are two clavicular elements on each side; the lower corresponds to the clavicle of See also:

• REP, REPP, or REPS

rep-tiles and higher vertebrates, whilst the up-per corresponds to the clavicle of teleostean fishes, and has been named by him "cleithrum." As stated above, there is strong evidence in favour of the view that some forms at least possessed in addition a "supracleithrum," corresponding to the supra-clavicle. of bony S fishes . The element often termed " cora- Coid " in these fossils ould be the scapula . he clavicles See also:

• REST (O. Eng. rest, reste, bed, cognate with other Teutonic forms, e.g. Ger. Rast, Riiste, rest, and probably Gothic Rasta, league, i.e. resting or stopping place)

rest on a D large discoidal, rhom- throughout. the interclavicle of Pmx, Premaxilla . Hy, Hyoidean cornu reptiles . Mx, Maxilla . P.S, Parasphenoid . The pectoral girdle Vo, Vomer . An,Angulare. of the living types of Na, Nasal . D, Dentale. batrachians is dis- S.e, Sphen-ethmoid . V, Foramen of exit tinguishable into a Fr, Frontal. of the trige- scapular, a coracoidal, Pa, Parietal. minal. and a' praecoracoidal E.Q Exoccipital . H, Of the optic. region .

In most of the Ep, Epiotic process . X, Of the pneumo- Caudata the scapular Pr.O, See also:

• PRO

Pro-otic. gastric and region alone ossifies, t.t, Tegmentympani. glosso-pharyn- but in the Ecaudata Sq, Squamosal. geal nerves. the coracoid is bony QQ J, Quadrato-jugal . Vr . Foramen by and a clavicle is fre- t', Pterygoid, an- which the or- quently developed over terror process. bito-nasal or the praecoracoid See also:

• CAR (Late Lat. carra)

car- Pt2, See also:

• INTERNAL

Internal process. first division of tilage . In these ba- Pts, Posterior or exter- the fifth passes trachians the pectoral nal process. to the nasal arch falls into two dis- Ca, See also:

• COLUMELLA, LUCIUS JUNIUS MODERATUS

Columella auris. cavity. tinet types—the arci- St, Stapes. ferous, in which the precoracoid (+clavicle) and coracoid are widely separated from each other distally and connected by an arched' cartilage (the ern: coracoid). the right usually overlapping the left ; and the firmi- sternal, in which both precoracoid and coracoid nearly abut on the median line, and are only narrowly separated by the more or less fused epicoracoids . The former type is exemplified by the toads and the lower Ecaudata, whilst the latter is characteristic of the true frogs (Ranidae), although when quite young these batrachians present a condition similar to that which persists throughout life in their lower relatives . A cartilage in the median line in front of the precoracokis, sometimes supported by a bony See also:

• STYLE
• STYLE (from Gr. a-6'1ms, a column; a different word from that used in literature, see below)

style, is the so-called omosternum; a large one behind the coracoids, also sometimes provided with a bony style, has been called the sternum . But these names will probably have to be changed when the homologies of these parts are better under-stood . The pelvic arch of some of the Stegocephalia contained a well ossified pubic element, whilst in all other batrachians only the ilium, or the ilium and the ischium are ossified . In the Ecaudata the ilium is greatly elongated and the pubis and ischium are flattened, discoidal, and closely applied to their See also:

• FELLOWS, SIR CHARLES (1799-1860)

fellows by their inner surfaces; the pelvic girdle looks like a pair of See also:

• TONGS (O. Eng. Lange, M. Eng. tonge, cf. Du. tang, Ger. Zange, from base tang, to bite, cf. Gr. SaKVeiv)

tongs . The long bones of the limbs consist of an See also:

• AXIS (Lat. for " axle ")

axis of cartilage; the extremities of the cartilages frequently undergo calcification and are thus converted into epiphyses . In the Ecaudata the radius and ulna coalesce into one bone .

The carpus, which remains cartilaginous in many of the Stegocephalia and Caudata, contains six to eight elements when the manus is fully developed, whilst the number is reduced in those forms which have only two or three digits . Except in some of the Stegocephalia, there are only four functional digits in the manus, but the Ecaudata have a more or less distinct rudiment of pollex; in the Caudata it seems to be the See also:

• OUTER

outer See also:

• DIGIT (Lat. digit us, finger)

digit which has been suppressed, as atavistic reappearance of a fifth digit takes place on the outer side of the Manus, as it does on the pes in those forms in which the toes are reduced to four . The usual number of phalanges is 2, 2, 3, 2 in the Stegocephalia and Caudata, 2, 2, 3, 3 in the Ecaudata . In the See also:

• FOOT

foot the digits usually number five, and the phalanges 2, 2, 3, 3, 2 in the Caudata, 2, 2, , 4, 3 in the Stegocephalia and Ecaudata . There are occasionally See also:

• INTERCALARY (from Lat. intercalare, to proclaim, calare, the insertion of a day in the calendar)

intercalary ossifications between the two distal phalanges (33) . There are usually nine tarsal elements in the Caudata; this number is reduced in the Ecaudata, in which the two bones of the proximal row (sometimes coalesced) are much elongated and form an additional segment to the greatly lengthened hind-limb, a sort of crus secundarium . In the Ecaudata also, the tibia and fibula coalesce into one bone, and two or three small bones on the inner side of the tarsus form what has been regarded as a rudimentary digit or " prehallux." Integument.—In all recent batrachians, the skin is naked, or if small scales are present, as in many of the Apoda, they are concealed in the skin . The extinct Stegocephalia, on the other hand, were mostly protected, on the ventral surface at least, by an See also:

• ARMOUR, PHILIP DANFORTH (1832-1901)

armour of overlapping round, See also:

• OVAL (Lat. ovum, egg)

oval, or rhomboidal scales, often very similar to those of Crossopterygian or ganoid fishes, and likewise disposed in trans-verse oblique lines converging forwards on the middle line of the belly . Sometimes these scales assumed the importance of scutes and formed a carapace, as in the batrachian armadillo " discovered by E . D . Cope . A few frogs have the skin of the back studded with stellate bony deposits Phyllomedusa, Nototrema), whilst two genera are remarkable for possessing a bony dorsal See also:

• SHIELD (0. Eng. scild, cf. Du. and Ger. Schild, Dan. Skjold; the origin is doubtful, but may be referred to the root seen in " shell " or " scale "; another suggestion connects it with Icel. skjalla, to clash, rattle; it is not connected with the Indo-Ger
• SHIELD, WILLIAM (1748—1829)

shield, See also:

• FREE

free from the vertebrae (Ceratorphrys) or ankylosed to 'them (Brachycephalus) .

None of the Stegocephalia appears to have been provided with claws, but some living batrachians (Onychodactylus, Xenopus, Hymenochirus) have the tips of some or all of the digits protected by a claw-like horny sheath . The integument of tailed and tailless batrachians is remarkable for the great abundance of follicular glands, of which there may be two kinds, each having a special secretion, which is always more or less acrid and irritating, and affords a means of See also:

• DEFENCE
• DEFENCE (Lat. defendere, to defend)

defence against the attacks of many carnivorous animals . A great See also:

• DEAL

deal has been A apparatus of Necturus maculosus . Hh, Hypo-hyal . Ep.br,Ep.b?,Ep.b3, Ch, Cerato-hyal . First, second Bb', First basi- and third epi- branchial. branchials . Bbl, Ossified second Gl, Glottis . basibranchial . published on the poisonous secretion of batrachians (34), which is utilized by the See also:

• INDIANS, NORTH AMERICAN

Indians of South America for poisoning their arrows . Some of the See also:

• POISON

poison-secreting glands attain a greater complication of structure and are remarkable for their large size, such as the so-called " parotoid " glands on the back of the See also:

• HEAD (in 0. Eng. heafad; the word is common to Teutonic languages; cf. Dutch hoofd, Ger. Haupt, generally taken to be in origin connected with Lat. caput, Gr. KerbOvi7)
• HEAD, SIR EDMUND WALKER, BART
• HEAD, SIR FRANCIS BOND, BART

head in toads and salamanders . In all larval forms, in the Caudata, and in a few of the Ecaudata (-Xenopus, for instance), the epidermis becomes modified in relation with the termination of sensory nerves, and gives rise to See also:

• ORGANS

organs of the same nature as those of the lateral line of fishes . In addition to diffuse pigment (mostly in the epidermis), the skin contains granular pigment stored up 2r' in cells, the chromatophores, restricted to the cutis, which are highly See also:

• MOBILE

mobile and send out r= branches which, by contraction and expansion, may rapidly alter the coloration, most batrachians being in this respect quite comparable to the famous chameleons .

Besides See also:

• WHITE
• WHITE, ANDREW DICKSON (1832– )
• WHITE, GILBERT (1720–1793)
• WHITE, HENRY KIRKE (1785-1806)
• WHITE, HUGH LAWSON (1773-1840)
• WHITE, JOSEPH BLANCO (1775-1841)
• WHITE, RICHARD GRANT (1822-1885)
• WHITE, ROBERT (1645-1704)
• WHITE, SIR GEORGE STUART (1835– )
• WHITE, SIR THOMAS (1492-1567)
• WHITE, SIR WILLIAM ARTHUR (1824--1891)
• WHITE, SIR WILLIAM HENRY (1845– )
• WHITE, THOMAS (1628-1698)
• WHITE, THOMAS (c. 1550-1624)

white (guanine) cells, the pigment includes See also:

• BLACK
• BLACK, ADAM (1784-1874)
• BLACK, JEREMIAH SULLIVAN (1810–1883)
• BLACK, WILLIAM (1841-1898)

black, See also:

• BROWN
• BROWN, CHARLES BROCKDEN (1771-181o)
• BROWN, FORD MADOX (1821-1893)
• BROWN, FRANCIS (1849- )
• BROWN, GEORGE (1818-188o)
• BROWN, HENRY KIRKE (1814-1886)
• BROWN, JACOB (1775–1828)
• BROWN, JOHN (1715–1766)
• BROWN, JOHN (1722-1787)
• BROWN, JOHN (1735–1788)
• BROWN, JOHN (1784–1858)
• BROWN, JOHN (1800-1859)
• BROWN, JOHN (1810—1882)
• BROWN, JOHN GEORGE (1831— )
• BROWN, ROBERT (1773-1858)
• BROWN, SAMUEL MORISON (1817—1856)
• BROWN, SIR GEORGE (1790-1865)
• BROWN, SIR JOHN (1816-1896)
• BROWN, SIR WILLIAM, BART
• BROWN, THOMAS (1663-1704)
• BROWN, THOMAS (1778-1820)
• BROWN, THOMAS EDWARD (1830-1897)
• BROWN, WILLIAM LAURENCE (1755–1830)

brown, yellow and red . The See also:

• GREEN, A
• GREEN, ALEXANDER HENRY (1832—1896)
• GREEN, DUFF (1791—1875)
• GREEN, JOHN RICHARD (1837—1883)
• GREEN, MATTHEW (1696-1737)
• GREEN, THOMAS HILL (1836-1882)
• GREEN, VALENTINE (1739–1813)
• GREEN, WILLIAM HENRY (.1825–1900)

green and See also:

• BLUE (common in different forms to most European languages)

blue, so frequent in frogs and newts, are merely subjective See also:

• COLOURS, MILITARY

colours, due to interference . On the mechanism of the change of See also:

• COLOUR (Lat. color, connected with celare, to hide, the root meaning, therefore, being that of a covering)

colour, cf . W . See also:

• BIEDERMANN, FRIEDRICH KARL (1812-1901)

Biedermann (35) . One of the interesting recent discoveries is that of the " hairy " frog (Trichobatrachus), in which the sides of the See also:

• BODY

body and limbs are covered with long villosities, the See also:

• FUNCTION

function of which is still unknown (36) . The nuptial horny asperities with which the See also:

• MALES

males of many batrachians are provided, syc for the purpose of clinging- to the See also:

• FEMALES

females, will be noticed below, under the heading Pairing and Oviposition . Dentition.—In the Microsauria and Branchiosauria among the Stegocephalia, as in the other orders, the hollow, conical or slightly curved teeth exhibit simple or only slightly folded walls . But in the Labyrinthodonta, grooves are more or less marked along the teeth and give rise to folds of the See also:

• WALL (O. Eng. weal, weall, Mid. Eng. wal, wane, adapted from Lat. vallum, rampart; the original O. Eng. word for a wall was wag or tenth)
• WALL, RICHARD (1694-1778)

wall which, extending inwards and ramifying, produce the complicated structure, exhibited by trans-verse sections, whence these batrachians de-rive their name; a somewhat similar complexity of structure is known in some holoptychian (dendrodont) Crossopterygian fishes . In the remarkable See also:

• SALAMANDER

salamander Autodax, the teeth in the jaws are compressed, See also:

• SHARP, GRANVILLE (1735-1813)
• SHARP, JAMES (1618-1679)
• SHARP, JOHN (1645-1714)
• SHARP, RICHARD (1759-1835)
• SHARP, WILLIAM (1749-1824)
• SHARP, WILLIAM (1856-1905)

sharp-edged, See also:

• LANCET (from Fr. lancette, dim. of lance, lance)

lancet shaped . The teeth are not implanted 7 in sockets, but become ankylosed with the Ivc bones that bear them, and are replaced by See also:

• FTC

Ftc . 13.—Ventral others developed at their bases .

Teeth are present in the jaws of all known Stegocephalia view of the head and Apoda and of nearly all Caudata, Siren and trunk of Ichthy- alone presenting plates of See also:

• HORN
• HORN (a common Teutonic word, cognate with Lat. cornu; cf. Gr. Kipas)
• HORN (Lat. cornu; corresponding terms being Fr. cor, trompe; Ger. Horn; Ital. corno)
• HORN, ARVID BERNHARD, COUNT (1664-1742)
• HORN, PHILIP DE MONTMORENCY, COUNT

horn upon the ophis glutinosus. gingival surfaces of the premaxillae and of Mn, Mandible. the dentary elements of the mandible . But Hy, Hyoid. they are nearly always absent in the lower Br', Br2, 13,4, See also:

• BRAN

Bran- jaw of the Ecaudata (exceptions in Hemichial arches. phractus, Amphignathodon, Amphodus, Cerato- GI, Glottis. batrachus, the male of Dimes pho nathus), many Tr, Trachea. of which (toads, for instance) are entirely Ivc, Inferior vena edentulous . cava . - There is great variety in the distribution V, Ventricle. of the teeth on the palate . They may occur Au, Auricles. simultaneously on the vomers, the palatines, Rsve, Lsvc, right the pterygoids and • the parasphenoid in and left supe- some of the Stegocephalia (Dawsonia, Seeleya, rior cavae . Acanthostoma), on the vomers, palatines and Ta, Truncus ar- parasphenoid in many salamandrids (Pletho- teriosus. dontinae and Desmognathinae), on the vomers, A o, Left aortic pterygoids and parasphenoid (some .Pelobates), arch. on the vomers and parasphenoid (Triprion, P.A . Right pulmon- Amphodus), whilst in the majority of othe