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 I  .—CROSSOPTERYGII Paired fins, at least the pectorals, lobate, having an endo-skeletal See also:

• AXIS (Lat. for " axle ")

axis more or less fringed with dermal rays . Mandibular See also:

• ARCH
• ARCH, JOSEPH (1826– )

arch suspended from the upper segment of the hyoid arch (hyostylic See also:

• SKULL

skull) . Splenial 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 See also:

• PRESENT

present . No supraoccipital bone . A pair of large jugular plates, sometimes with small lateral plates and an anterior azygous See also:

• ELEMENT (Lat. elementum)

element, See also:

• DEVELOPED

developed in the branchiostegal membrane between the mandibular rami . See also:

• HEART
• HEART, LUNG

Heart with a' contractile, multivalvular conus arteriosus; See also:

• INTESTINE (Lat. intestinus, internal, usually in neuter plural intestina. from intus, within)

intestine with a See also:

• SPIRAL

spiral See also:

• VALVE (Lat. valva, a leaf of a double or folding door, allied to volvere, to roll, as of a door on its hinges)

valve; See also:

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

air-See also:

• BLADDER (from A.S. blaeddre, connected with bl¢wan, to blow, cf. Ger. blase)

bladder with pneumatic duct communicating with the ventral See also:

• SIDE
• SIDE (mod. Eski Adalia)

side of the See also:

• OESOPHAGUS (Gr. o'lvca=I will carry, and r/)ayeiv, to eat)

oesophagus . Maxillary bone large, toothed, bordering the mouth . Bones of the upper See also:

• SURFACE

surface of the skull mostly paired . See also:

• PECTORAL

Pectoral arch with both clavicle (so-called infra-clavicle) and cleithrum . Ventral fins inserted far back . With few exceptions (tail of Coelacanthidae, dorsal and caudal fins of Polypteridae) the dermal rays of the unpaired fins more numerous than their endo-skeletal supports, a See also:

• PRIMITIVE

primitive See also:

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

character also found in the See also:

• LOWER

lower Ganoids, but disappearing in the higher . SUB-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 I.—OSTEOLEPIDA (Including the Haplistia, Rhipidistia and Actinistia.) Pectoral fins obtusely or acutely lobate, articulating with the pectoral 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 by a single basal endo-skeletal element .

Nostrils on the lower side of the snout . Two dorsal fins . Families: Osteolepidae, Rhizodontidae, Holoptychidae, Coelacanthidae . The scales may be rhombic and thickly coated with ganoine (Osteolepidae) or See also:

• CYCLOID (from Gr. iciidws, circle, and ennos, form)

cycloid . The vertebral axis is strongly heterocercal in the Osteolepidae and Holoptychidae, and diphycercal or intermediate between the heterocercal and the diphycercal types in the other families; usually acentrous, sometimes with 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-like calcifications (some of the Rhizodontidae) . In the Holoptychidae the pectoral fin is extremely similar to that of the Dipneusti of the See also:

• FAMILY

family Dipteridae, which they resemble closely in See also:

• FORM (Lat. forma)

form and scaling . Their See also:

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

teeth are remarkable for their complicated structure, resembling that of the Labyrinthodont Batrachians . A pineal foramen is present between the frontal bones in most of the Rhizodontidae . The Osteolepidae were mostly moderate-sized fishes, the largest (Megalichthys) measuring about 4 ft. in length . These Crossopterygians first appear in the Lower Devonian, are abundant in the Upper Devonian, Carboniferous and See also:

• PERMIAN

Permian; in later periods they are represented only by the more specialized Coelacanthidae, which appear in the Lower Carboniferous, and persist as See also:

• LATE

late as the Upper See also:

• CHALK

Chalk . SUB-ORDER II.—CLADISTIA Pectoral fin obtusely lobate, with three basal endo-skeletal elements . Nostrils on the upper side of the snout .

A single dorsal fin, formed of a See also:

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

series of detached rays . A single family: Polypteridae . The existing Crossopterygians which form this sub-order differ very considerably from the See also:

• EXTINCT

extinct Osteolepida, perhaps quite as much as these differ from the Dipneusti . The ventral fins are not lobate, the vertebral See also:

• COLUMN (Lat. columna)

column is well ossified and its termination is of the diphycercal type . Spiracles, covered by bony valves, are present on the upper surface 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 . The dorsal fin is unique among fishes, being formed of detached rays consisting of a spine-like fulcra! See also:

• SCALE
• SCALE (1) A

scale supporting the fringes of the See also:

• RAY (Lat. raia)
• RAY (or WRAY, as he wrote his name till 1670), JOHN (1628-1705)

ray; these rays have been regarded, erroneously, as representing so many distinct fins, or " finlets." The scales are bony, rhombic and thickly coated with ganoine . The Polypteridae are confined to tropical See also:

• AFRICA
• AFRICA, ROMAN

Africa and the See also:

• NILE
• NILE, BATTLE OF THE
• NILE, SOBAT

Nile, and represented by two genera: Polypterus and Calamichthys, the former moderately elongate and provided with ventral fins, the latter serpentiform and devoid of ventrals . We now know ten See also:

• SPECIES

species of Polypterus, from the Nile, the See also:

• CONGO

Congo, the See also:

• RIVERS
• RIVERS, ANTHONY WOODVILLE, or WYDEVILLE, 2ND EARL (c. 1442—1483)
• RIVERS, EARL
• RIVERS, RICHARD SAVAGE, 4TH EARL (c. 1660—1712)

rivers of See also:

• WEST
• WEST, BENJAMIN (1738-1820)
• WEST, NICHOLAS (1461-1533)

West Africa, and lakes See also:

• CHAD
• CHAD [CEADDA], SAINT (d. 672)

Chad, See also:

• RUDOLF (otherwise known as Basso NOROK and Gannon)

Rudolf and See also:

• TANGANYIKA (a name said by V. L. Cameron to signify a " mixing-place ")

Tanganyika, and one of Calamichthys, which inhabits West Africa from the See also:

• NIGER
• NIGER, GAIUS PESCENNIUS

Niger See also:

• DELTA (from the shape of the Gr. letter A, delta, originally used of the mouth of the Nile)

delta to the Chiloango . The largest species of Polypterus reach a length of nearly 4 ft . The 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 are provided with an See also:

• EXTERNAL

external opercular gill very similar to the gills of larval salamanders . The air-bladder acts as an See also:

• ACCESSORY

accessory breathing See also:

• ORGAN

organ, although these fishes are not known ever to leave the See also:

• WATER

water . The development is stated by the late J .

S . Budgett to be even more Batrachian-like than that of the Dipneusti, but the results of the study of the material collected by him shortly before his See also:

• DEATH

death have not yet been published .