See also:

• APTERA (Greek for " wingless ")

APTERA (See also:

• GREEK
• GREEK, ETRUSCAN AND

Greek for " wingless ")  , a See also:

• TERM

term in zoological See also:

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

classification applied by See also:

• LINNAEUS

Linnaeus to various See also:

• GROUPS
• GROUPS, THEORY

groups of wingless arthropods, including some of the See also:

• INSECTS

insects, the centipedes, the millipedes, the See also:

• ARACHNIDA

Arachnida (scorpions, See also:

• SPIDERS

spiders, &c.) and the See also:

• CRUSTACEA

Crustacea . In 3 . 4 . 5 . See also:

• MODERN

modern See also:

• ZOOLOGY (from Gr. Nov, a living thing, and ?byos, theory)

zoology the term has become restricted to the lowest 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 of the class See also:

• HEXAPODA (Gr. 4, six, and gobs, foot)

Hexapoda or true insects . This order includes the bristle-tails and the springtails . Many wingless insects—such as lice, fleas and certain See also:

• EAR (common Teut.; O.E. are, Ger. Ohr, Du. oor, akin to Lat. auris, Gr. ovs)

ear-wigs and cockroaches—are placed in various orders together with winged insects to which they show evident relationships . In such cases the See also:

• ABSENCE (Lat. absentia)

absence of wings must be regarded as secondary —due to a parasitic or other See also:

• SPECIAL

special manner of See also:

• LIFE

life . But the bristle-tails and springtails, which See also:

• FORM (Lat. forma)

form the modern order See also:

• APTERA (Greek for " wingless ")

Aptera, are all without any trace of wings, and, on See also:

• ACCOUNT
• ACCOUNT (through O. Fr. acont, Late Lat. comptum, cornputare, to calculate)

account of several remarkable archaic characters which they exhibit, there is See also:

• REASON (Lat. ratio, through French raison)

reason for believing that they are primitively wingless—that they represent an See also:

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

early off-shoot which sprang from the ancestral stock of the Hexapoda before See also:

• ORGANS

organs of See also:

• FLIGHT

flight had been acquired by the class . Characters.—In addition to the See also:

• COMPLETE

complete absence of wings and of See also:

• METAMORPHOSIS

metamorphosis, the Aptera are characterized by See also:

• PECULIAR

peculiar elongate mandibles (See also:

• FIGS

figs . 1, Mn.; 2, 4), with toothed See also:

• APEX

apex and sub-apical grinding See also:

• SURFACE

surface, like those of certain Crustacea; by the presence between the mandibles and maxillae of a pair of appendages (superlinguae or maxillulae), fig . 1, Mxl., which are absent or vestigial in all other insects; and, in most genera, by the presence in the adult .of abdominalappendagesused for locomotion, these latter varying in number from one to nine pairs .

- Among peculiarities of the See also:

• INTERNAL

internal organs the segmental arrangement of the ovaries in most members of the order is noteworthy . Many Aptera are covered with flattened scales like those of moths . Classification.—The Aptera are divided into two divergent sub-orders, the See also:

• THYSANURA

Thysanura (q.v.) or bristle-tails, and the Collembola or springtails . Thysanura.—The bristle- tails have an See also:

• ABDOMEN (a Latin word, either from abdere, to hide, or from a form adipomen, from adeps, fat)

abdomen of eleven segments, the tenth usually carrying a pair of See also:

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

long many-jointed tail-feelers (cerci, fig . 1, x.) ; sometimes a median, jointed tail-appendage is also See also:

• PRESENT

present . To these feelers the popular name is due . There may also be abdominal appendages—in the form of See also:

• SIMPLE

simple unjointed stylets (fig. s, ii.-ix.), accompanied by paired eversible sacs, probably See also:

• RESPIRATORY

respiratory in See also:

• FUNCTION

function—on eight (or fewer) other abdominal segments . 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 of a bristle-tail carries a pair of See also:

• COMPOUND
• COMPOUND (from Lat. componere, to combine or put together)

compound eyes and a pair of elongate many-jointed feelers . The See also:

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

air-See also:

• TUBE (Lat. tuba)

tube See also:

• SYSTEM

system is See also:

• DEVELOPED

developed in varying degree in different bristle-tails, the number of pairs of spiracles being three (See also:

• CAMPODEA

Campodea), nine (Machilis), ten (Lepisma), or eleven (Japyx) . Four families of Thysanura are usually recognized . In theMachilidae and Lepismidae (these two families are known as the Ectotrophi) the maxillae are like those of typical biting insects, and there is a median tail-bristle in addition to the paired cerci; while in the Campodeidae and Japygidae (which form the See also:

• GROUP

group Entotrophi) the jaws are apparently sunk in the head, through a deep inpushing at the mouth, and there is no median tail-bristle . The cerci in Japyx are not, as usual, jointed feelers, but strong, curved appendages forming a forceps as in earwigs .

Collembola.—In springtails, or Collembola, the jaws are sunk into the head, as in the entotrophous Thysanura; the head carries a pair of feelers with not more than six (usually four) segments, and there are eight (or fewer) distinct simple eyes on each See also:

• SIDE
• SIDE (mod. Eski Adalia)

side of the head (fig . 2, 1, 2) . These are in some genera From See also:

• CARPENTER, LANT (1780-1840)
• CARPENTER, MIRY (1807-1877)
• CARPENTER, WILLIAM BENJAMIN (1813-1885)

Carpenter, Proc . R . Dub . See also:

• SOC

Soc. vol. xi . 1 . Isotoma hibernica . Side view . 2 . ,, Ocelli and See also:

• POST

post-antennal See also:

• ORGAN

organ of right side . Tip of terminal antennal segment with antennal organ .

Mandible . Tip of See also:

• LEFT

left See also:

• DENS, PETER (1690-1775)

dens with mucro . See also:

• OUTER

Outer view 6 . 7• like the single elements (ommatidia) of a compound See also:

• INSECT

insect See also:

• EYE
• EYE (O. Eng. edge, Ger. Auge; derived from an Indo-European root also seen in Lat. oc-ulus, the organ of vision (q.v.)

eye, in others like simple ocelli . The abdomen consists of six segments only . The first of these usually carries a ventral tube, furnished with paired eversible sacs which assist the insects in walking on smooth surfaces, and perhaps serve also as organs for breathing . From the researches of V . Willem it appears that the viscid fluid which causes the adherence of the ventral tube is secreted by a pair of glands in the head whose ducts open into a superficial groove leading from the second maxillae backward to the tube on the first abdominal segment . The third abdominal segment usually carries a pair of See also:

• SHORT, FRANCIS JOB (1857– )

short appendages whose basal segments are fused together; this is the " catch " (fig . 2, 7), whose function is to hold in See also:

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

place the " See also:

• SPRING (from " to spring," " to leap or jump up," " burst out," O. Eng., springau, a common Teut. word, cf. Ger. springer, possibly allied to Gr. QnrFpxecOac, to move rapidly)

spring," which is formed by the See also:

• FOURTH

fourth pair of abdominal appendages—also with fused basal segments . In most Collembola the spring appears to belong to the fifth abdominal somite, but Willem, by study of the muscles, has shown that it really belongs to the fourth . The fused basal segments of the appendages form the " manubrium " of the spring, which carries the two " dentes " (usually elongate From Knowledge .

Mx', Mx2, 1st and 2nd maxillae . ii.-x, Appendages on 2nd to loth ab- dominal segments . The ever- sible sacs on the abdominal segments are shown, some protruded and some retracted . Ovp, Ovipositor . Mn, Mandible, and Mxl. maxillula, dissected out of head . See also:

• HIND

Hind-See also:

• FOOT

foot with claws . X 240 . Entomobrya anomala . Catch . and flexible), each with a " mucro " at its tip (fig . 2, 5) . The fifth abdominal segment is the genital, and the See also:

• SIXTH

sixth the anal somite .

The spring serves the Collembola which possess it as an efficient leaping-organ (see See also:

• SPRINGTAIL

SPRINGTAIL) . But in some genera it is greatly reduced and in many quite vestigial . Most springtails are without air-tubes, and breathe through the See also:

• GENERAL
• GENERAL (Lat. generalis, of or relating to a genus, kind or class)

general cuticle of the See also:

• BODY

body . But in one See also:

• FAMILY

family (Sminthuridae) a spirade, opening on either side between the head and the prothorax, leads to a branching system of air-tubes . The Sminthuridae are further characterized by the globular abdomen, which shows but little See also:

• EXTERNAL

external trace of segmentation, and by the well-developed spring . In the Entomobryidae the body is elongate and clearly segmented, but the dorsal region (tergum) of the prothorax is much reduced and the head downwardly directed; the spring is well developed . In the Achorutidae the head is forwardly directed, the tergum of the prothorax conspicuous, and the spring small or vestigial . In many genera of springtails a curious post-antennal organ, consisting of sensory structures (often complex in form) surrounded by a See also:

• FIRM

firm 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, is to be noticed on the cuticle of the head between the eyes and the feelers . It may be of use as an organ of See also:

• SMELL (connected etymologically with " smoulder " and " smoke ")

smell . Other sensory organs occur on the third and fourth antennal segments in the Achorutidae and, Entomobryidae (fig . 2, 3) . See also:

• DISTRIBUTION (Lat. distribuere, to deal out)

Distribution and Habits.—The Aptera are probably the most widely distributed of all insects .

Among the bristle-tails we find the genus Machilis, represented in See also:

• EUROPE

Europe (including the See also:

• FAEROE (also written FAROE or THE FAEROES, Danish Faeroerne or Fliroerne, "the sheep islands ")

Faeroe Islands) and in See also:

• CHILE, or CHILI (derived, it is said, from the Quichua chin , cold, or tchili, snow)

Chile; while Campodea lives high on the mountains and in the deepest caves . The springtails have even a wider distribution . The genus Isotoma, for example, has some of its numerous See also:

• SPECIES

species in regions so remote as See also:

• ALASKA

Alaska, See also:

• FRANZ, ROBERT (1815-1892)

Franz Josef See also:

• LAND

Land, the See also:

• SANDWICH
• SANDWICH, EDWARD MONTAGU, or MOUNTAGU, 1ST EARL OF (1625–1672)
• SANDWICH, JOHN MONTAGU, 4TH EARL OF (1718–1792)

Sandwich Islands, the See also:

• SOUTH
• SOUTH, ROBERT (1634–1716)

South Orkneys, See also:

• GRAHAM, SIR GERALD (1831–1899)
• GRAHAM, SIR JAMES ROBERT GEORGE
• GRAHAM, SYLVESTER (1794-1851)
• GRAHAM, THOMAS (1805-1869)

Graham Land, Kerguelen and South See also:

• VICTORIA
• VICTORIA (or VITTORIA), TOMMASSO LUDOVICO DA (C. I540-C. 1613)
• VICTORIA [ALEXANDRINA VICTORIA]

Victoria Land . As it is unlikely that these delicate insects could be transported across See also:

• SEA (in O. Eng. sae, a common Teutonic word; cf. Ger. See, Dutch Zee, &c.; the ultimate source is uncertain)
• SEA, COMMAND OF THE

sea-channels, their wide and discontinuous range suggests both their See also:

• GREAT

great antiquity and the former existence of See also:

• CONTINENTAL

continental tracts over which they may have travelled to their present stations . Springtails and bristle-tails live in See also:

• DAMP

damp concealed places—under stones or See also:

• TREE (0. Eng. treo, treow, cf. Dan. tree, Swed. Odd, tree, trd, timber; allied forms are found in Russ. drevo, Gr. opus, oak, and 36pv, spear, Welsh derw, Irish darog, oak, and Skr. dare, wood)
• TREE, SIR HERBERT BEERBOHM (1853- )

tree-hark, in See also:

• MOSS

moss, and in the decaying See also:

• VEGETABLE

vegetable or See also:

• ANIMAL
• ANIMAL (Lat. animalis, from anima, breath, soul)

animal See also:

• MATTER

matter which serves as 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 for most of them . Some species, however, eat fresh plant-tissues . A species of bristle-tail (Machilis maritima) and quite a number of springtails haunt the sea-See also:

• COAST (from Lat. costa, a rib, side)

coast at or below high-See also:

• WATER

water See also:

• MARK
• MARK, CARL (1858– )
• MARK, GOSPEL OF ST
• MARK, ST

mark . In such localities many thousands of individuals may sometimes be found associated together . The insect See also:

• FAUNA

fauna of See also:

• LIMESTONE

limestone caves both in 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 is largely composed of Aptera, especially Collembola . See also:

• GEOLOGICAL

Geological See also:

• HISTORY

History.—A supposed Thysanuran from the See also:

• SILURIAN

Silurian of New See also:

• BRUNSWICK
• BRUNSWICK (Ger. Braunschweig)
• BRUNSWICK, KARL WILHELM FERDINAND, DUKE OF (1735-18o6)

Brunswick has been described by G . F . See also:

• MATTHEW, GOSPEL OF ST
• MATTHEW, ST (MaOOaior or MarOaIos, probably a shortened form of the Hebrew equivalent to Theodorus)
• MATTHEW, TOBIAS

Matthew, and another genus from the See also:

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

French Carboniferous by C .

See also:

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

Brongniart . Not till the See also:

• TERTIARY

Tertiary do we find remains of Aptera in any quantity, species both of living and See also:

• EXTINCT

extinct genera being represented in the See also:

• AMBER

amber . Development.—The embryonic development of several genera of Aptera, which has been carefully studied, will be more suitably described in comparison with that of other insects than here (see HEXAPODA) . BIBLIOGRArny.—The modern study of the Aptera may be said to date from the classical See also:

• MEMOIRS

memoirs of 1' . Tullbcrg, " Sveriges Podurider," in Kongl . Svensk Vetensk . Akad . Mandl. x., 1872, and See also:

• SIR

Sir J . Lubbock (See also:

• LORD
• LORD (O. Eng. hldford, i.e. hldfweard, the warder or keeper of bread, hlIf, loaf; the word is not represented in any other Teutonic language)
• LORD, JOHN (1810-1894)

Lord See also:

• AVEBURY
• AVEBURY, JOHN LUBBOCK, 1ST BARON (1834– )

Avebury), " Monograph of the Collembola and Thysanura," See also:

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

Ray Society, 1873 . In these, full references to the older literature will be found . Subsequently our knowledge of the Thysanura has been markedly advanced by J . T .

Oudemans, Bijdrage tot de Kennis den Thysanura en Collembola (See also:

• AMSTERDAM
• AMSTERDAM (NEw AMSTERDAM)

Amsterdam, 1888); B . Grassi. who published between 1885 and 1889 a See also:

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

series of memoirs entitled " I progenitori dei Miriapodi e degli Insetti," in the Atli Accad. di Scienz . Nat . See also:

• CATANIA (Gr. Katane, Rom. Catinal)

Catania, and the Memor . R . Accad. dei Lincei; and V . Willem, whose " Recherches sur See also:

• LES

les Collemboles et les Thysanoures," in See also:

• MENA, JUAN DE (1411–1456)
• MENA, PEDRO DE (d. 1693)

Mena . Cour . Acad . See also:

• ROY, WILLIAM (1726-1790)

Roy . Belgique, lviii., 1900, are indispensable to the student . In addition to this See also:

• WORK

work of Willem, valuable anatomical papers on Collembola have been published by H .

J . See also:

• HANSEN, PETER ANDREAS (1795-1874)

Hansen (Zool . Anz. xvi., 1893), J . W . Folsom (See also:

• BULL
• BULL, GEORGE (1634–1710)
• BULL, JOHN (c. 1562–1628)
• BULL, OLE BORNEMANN (18ro-188o)

Bull . Muse Comp . Anat . Harn See also:

• XXXV

xxxv., 1899) . C . Bbrner (Zool . Anz . 'goo), and K .

Absolon (Zool . Anz. See also:

• XXIII

xxiii. and See also:

• XXIV

xxiv., 1900, 1901), the twolatter writers having paid especial See also:

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

attention to the peculiar post antennal and antennal sense-organs of springtails . Absolon has also written on the Collembola of caves . These writers, with H . Schott, C . Schaffer and others, have published many systematic papers on Collembola, as has F . Silvestri on Thysanura . See also:

• BRITISH

British species are mentioned in Lubbock's monograph ; for See also:

• RECENT

recent additions see G . H . Carpenter and W . See also:

• EVANS, CHRISTMAS (1766-1838)
• EVANS, EVAN HERBER (1836-1896)
• EVANS, OLIVER (1755–1819)
• EVANS, SIR GEORGE DE LACY (1787–1870)
• EVANS, SIR JOHN (1823-1908)

Evans (Prot . R .

Phys . Soc . Edinb. xiv., 1899, and xv., 1903) . (G . H .