Page:EB1911 - Volume 21.djvu/185

Rh and feet with two primary papillae on the anterior side and one on the posterior side; outer jaw with one minor tooth at the base of the main tooth, inner jaw with no interval between the large tooth and the series of small ones; last fully developed leg of the male with enlarged crural gland opening on a large papilla placed on its ventral surface, coxal organs absent; the nephridial openings of the 4th and 5th pairs of legs are placed in the proximal spinous pad. Genital opening subterminal, behind the last pair of fully developed legs; oviduct without receptacula seminis or receptacula ovorum; the terminal unpaired portion of vas deferens short. Ova of considerable size, but with only a small quantity of yolk. The embryos in the uterus are all nearly of the same age, except for a month or two before birth, when two broods overlap.

The following species are aberrant in respect of these characters: Peripatus (Opisthopatus) cinctipes, Purcell (Cape Colony and Natal), presents a few Australasian features; there is a small receptaculum seminis on each oviduct, some of the legs are provided with well developed coxal organs, the feet have one anterior, one posterior and one dorsal papilla, and the successive difference in the ages of the embryos in the uterus, though nothing like that found in the neotropical species, is slightly greater than that found in other investigated African species. Several pairs of legs in the middle region of the body are provided with enlarged crural glands which open on a large papilla. Male with four accessory glands, opening on each side of and behind the genital aperture. P. thollons, Bouvier, (Equatorial West Africa [Gaboon]), shows some neotropical features; there are 24 to 25 pairs of legs, the genital opening is between the penultimate legs, and though there are only three spinous pads the nephridial openings of the 4th and 5th legs are proximal to the 3rd pad, coxal organs are present, and the jaws are of the neotropical type, the oviducts have receptacula seminis. The following South African species may be mentioned: P. capensis (Grube), with 17 (rarely 18) pairs of claw-bearing legs; P. balfouri (Sedgw.) with 18 (rarely 19) pairs; P. moseleyi (Wood-M.), with 20 to 24 pairs.

Australasian Species.—With 14, 15 or 16 pairs of claw-bearing ambulatory legs, with three spinous pads on the legs, and nephridial opening of the 4th and 5th legs on the proximal pad, feet with one anterior, one posterior and one dorsal primary papilla; inner jaw without diastema, outer with or without a minor tooth. Last leg of the male with or without a large white papilla on its ventral surface for the opening of a gland, and marked papillae for the crural glands are sometimes present on other legs of the male; well-developed coxal glands absent. Genital opening between the legs of the last pair; oviducts with receptacua seminis, without receptacula ovorum; the terminal portion of the vas deferens long and complicated; the accessory male glands open between the genital aperture and the anus, near the latter. Ova large and heavily charged with yolk, and provided with a stoutish shell. The uterus appears to contain embryos of different ages. Specimens are recorded from West Australia, Queensland, New South Wales, Victoria and New Zealand. The Australasian species are in some confusion. The number of claw-bearing legs varies from 14 to 16 pairs, but the number most often found is 15. Whether the number varies in the same species is not clear. There appears to be evidence that some species are occasionally or normally oviparous, and in the supposed oviparous species the oviduct opens at the end of a papilla called from its supposed function an ovipositor, but the oviparity has not yet been certainly proved as a normal occurrence. Among the species described may be mentioned P. leuckarti (Saenger), P. insignis (Dendy), P. oviparus (Dendy), P. viridimaculatus (Dendy), P. novae zealandiae (Hutton), but it is by no means certain that future research will maintain these. Mr J. J. Fletcher, indeed, is of opinion that the Australian forms are all varieties of one species, P. leuckarti.

Neotropical Species.—With three to five spinous pads on the legs, nephridial opening of the 4th and 5th legs usually proximal to the 3rd pad, and feet either with two primary papillae on the anterior side and one on the posterior, or with two on the anterior and two on the posterior; outer jaw with small minor tooth or teeth at the base of the main tooth, inner jaw with diastema. A variable number of posterior legs of the males anterior to the genital opening with one or two large papillae carrying the openings of the crural glands; well-developed coxal organs present on most of the legs. The primary papillae usually divided into two portions. Genital opening between the legs of the penultimate pair; oviduct provided with receptacula seminis and ovorum; unpaired part of vas deferens long and complicated; accessory organs of male opening at the sides of the anus. Ova minute, with little food-yolk; embryos in the uterus at very different stages of development. The number of legs usually if not always variable in the same species; the usual number is 28 to 32 pairs, but in some species 40 to 43 pairs are found. The neotropical species appear to fall into two groups: (1) the so-called Andean species, viz. those which inhabit the high plateaus or Pacific slope of the Andes; in these there are 4 (sometimes 5) pedal papillae, and the nephridial openings of the 4th and 5th legs are on the third pad; and (2) the Caribbean species, viz. the remaining neotropical species, in which there are 3 papillae on the foot and the nephridial openings of the

4th and 5th legs are between the 3rd and 4th pads. The Andean species are P. eisenii (Wh.), P. tuberculatus (Bouv.), P. lankesteri (Bouv.), P. quitensis (Schm.), P. corradi (Cam.), P. cameranoi (Bouv.) and P. balzani (Cam.). Of the remaining species, which are the majority, may be mentioned P. edwardsii (Blanch), P. jamaicensis (Gr. and Cock.), P. trinidadensis (Sedgw.), P. torquatus (Ken.), P. im thurmi (Scl.).

New Britain Peripatus.—With 22 to 24 pairs of claw-bearing legs, with three spinous pads on the legs, and nephridial openings of legs 4 and 5 (sometimes of 6 also) on the proximal pad; feet with one primary papilla on the anterior, one on the posterior side, and one on the dorsal side (median or submedian); outer jaw with a minor tooth, inner jaw without diastema; crural glands absent; well-developed coxal organs absent. Genital opening subterminal behind the last pair of legs; oviduct with receptaculum seminis, without receptaculum ovorum; unpaired part of vas deferens very short; accessory glands two, opening medianly and dorsally. Ova small, .1 mm. in diameter, with little yolk, and the embryos provided with large trophic vesicles (Willey). Embryos in the uterus of very different ages, and probably born all the year round. One species only known, P. novae britanniae (Willey).

Sumatran Peripatus.—Peripatus with 24 pairs of ambulatory legs, and four spinous pads on the legs. The primary papillae of the neotropical character with conical bases. Generative opening between the legs of the penultimate pair. Feet with only two papillae. Single species. P. sumatranus (Sedgw.). The existence of this species is doubtful.

Peripatus from the Malay Peninsula.—With 23 to 25 pairs of claw-bearing legs, four spinous pads on the legs, and nephridial openings of legs 4 and 5 in the middle of the proximal pad or on its proximal side; feet with two primary papillae, one anterior and one posterior; outer jaw with two, inner jaw with two or three minor teeth at the base of the main tooth, separated by a diastema from the row of small teeth; crural glands present in the male only, in the two pairs of legs preceding the generative opening; coxal glands present. Genital opening between the penultimate legs; oviduct with receptacula seminis and ovorum; unpaired part of vas deferens long; male accessory glands two, opening medianly between the legs of the last pair. Ova large, with much yolk and thick membrane, like those of Australasian species; embryos with slit-like blastopore and of very different ages in the same uterus, probably born all the year round. The species are P. weldoni (Evans), P. horsti (Evans) and P. butleri (Evans). It will thus be seen that the Malay species, while resembling the neotropical species in the generative organs, differ from these in many features of the legs and feet, in the important characters furnished by the size and structure of the ovum, and by their early development.

.—F. M. Balfour, “The Anatomy and Development of P. capensis,” posthumous memoir, edited by H. N. Moseley and A. Sedgwick, ''Quart. Journ. Mic. Sci.'' vol. xxiii. (1883); E. L. Bouvier, “Sur l'organisation du Peripatus tholloni, Bouv.,” Comptes rendus, cxxvi. 1358-1361 (1898); “Contributions à l'histoire des Péripates Americains,” ''Ann. de la société entomologique de France'', lxviii. 385-450 (1899); “Quelques observations sur les onychophores du musée britannique,” ''Quart. Journ. Mic. Sci'' xliii. 367 (1900); A. Dendy, “On the Oviparous Species of Onychophorea,” ''Quart. Journ. Mic. Sci.'' xlv. 362 (1902); R. Evans, “On Onychophora from the Siamese Malay States,” ''Quart. Journ. Mic.'' Sci. xliv. 473 (1901), and “On the Development of Ooperipatus,” ibid. xlv. 1 (1901); J. J. Fletcher, “On the Specific Identity of the Australian Peripatus, usually supposed to be P. leuckarti, Saenger,” ''Proc. Linn. Soc. New South Wales'', x. 172 (1895); E. Gaffron, “Beiträge z. Anat. u. Physiol. v. Peripatus,” Th. 1 and 2, ''Zool. Beiträge'' (Schneider), i. 33, 145; L. Guilding, “Mollusca caribbaeana: an account of a new genus of Mollusca,” ''Zool. Journ.'' ii. 443, pl. 14 (1826); reprinted in Isis, xxi. 158, pl. ii. (1828); H. N. Moseley, “On the Structure and Development of Peripatus capensis,” ''Phil. Trans.'' (1874); R. I. Pocock, “Contributions to our Knowledge of the Arthropod Fauna of the West Indies,” pt. 2, Malacopoda, &c, ''Journ. Linn. Soc.'' xxiv. 518; W. F. Purcell, “On the South African Species of Peripatus,” &c., Annals of the South African Museum, i. 331 (1898-1899); and “Anatomy of Opisthopatus cinctipes,” ibid. vol. ii. (1900); W. L. Sclater, “On the Early Stages of the Development of a South American Species of Peripatus,” ''Quart. Journ. of Mic. Sci.'' xxviii. 343-361 (1888); A. Sedgwick, “A Monograph of the Development of Peripatus capensis” (originally published in various papers in the Quart. Journ. Mic. Sci., 1885-1888); Studies from the ''Morphological Lab. of the University of Cambridge'', iv. 1-146 (1889); “A Monograph of the Species and Distribution of the Genus Peripatus, Guilding,” ''Quart. Journ. Mic. Sci.'' xxviii. 431-494 (1888); L. Sheldon, “On the Development of Peripatus novae zealandiae,” pts. 1 and 2, ''Quart. Journ. Mic. Sci.'' xxviii. and xxix. (1888 and 1889). The memoirs quoted by Sclater, Sedgwick and Sheldon are all reprinted in vol. iv. of the Studies from the ''Morphological Lab. of the University of Cambridge'', vol. iv. (Cambridge University Press, 1889). T. Steel, “Observations on Peripatus,” ''Proc. Linn. Soc. New South Wales'', p. 94 (1896); A. Willey, “The Anatomy and Development of P. novae britanniae,” Zoological Results, pt. 1, pp. 1-52 (Cambridge, 1898).
 * (Author:Adam Sedgwick (1854-1913))