MTRIAPODA 



463 



The Onychophora live under bark and stones and in other damp, 

 dark places and feed on insects and other small animals. 



History. Peripatus was first described in 1825 and classified, because 

 of its slug-like appearance, with the mollusks. It was, however, soon after 

 placed among the worms and in 1851 was made one of the 

 subdivisions of annelids by Grube, to which he gave the 

 name Onychophora. Burmeister in 1856 placed the 

 group between the annelids and the arthropods, and 

 Moseley in 1874 finally demonstrated its relationship to 

 the latter group by showing the presence of tracheae. 



The division contains 2 families with about 12 

 genera and 75 species, which are found in the Malay 

 Peninsula, the East Indies, Australia, New Zealand, Af- 

 rica, South and Central America, and the West Indies. 



^~:'lz&~'~. 



--ife 



FAMILY PEBIPATIDAE. 



Sexual orifice between the penultimate pair of 

 legs; 14 annulations to a somite on the back: tropical 

 America; East Indies; tropical Africa; about 5 genera 

 and 50 species. 



Peripatus Guilding. Number of pairs of legs from 

 23 to 43, but is variable in the same species; legs with 

 4 to 7 spinous pads; feet with 3 to 7 distal papillae; 

 eggs minute; embryo with placenta: about 40 species. 



P. (Oroperipatus Cockerell) eiseni* Wheeler (Fig. 

 722). Length 40 to 57 mm.; number of pairs of 

 legs 23 to 29 ; color reddish-brown : from Tepic, Mexico, 

 to Brazil. 



DIVISION 2. MYRIAPODA.f 



Tracheates with a distinct head and a trunk which is made up of a 

 large number of similar segments, each of which usually bears one or two 

 pairs of jointed appendages. The number of segments may vary from 

 eleven in Glomeris and Polyxenus to one hundred and seventy-three in 

 certain Geophilidae. The legs end each in a single claw, except in the 

 Symphyla, in which each leg has two claws. The appendages of the 

 head consist of a pair of segmented antennae, a pair of mandibles, and 

 one or two pairs of maxillae. The mandibles are without palps and 



* See "A New Peripstus from Mexico," by W. M: Wheeler, Jour. Morph., 

 Vol. 15, 1899. 



t See "The Myriapoda of North America," by H. C. Wood, Jr., Trans. Am. Phil. 

 Soc., Vol. 13, p. 137, 1865. "The Classification of the Myriapoda," by J. S. Kingsley, 

 Am. Nat., Vol. 22, p. 1118, 1888. "The Myriapoda of North America," by C. H. 

 Bollman, Bull. No. 46, U. S. Nat. Mus., 1893. "Myriapoda," by C. Verhoeff, Bronn'sv 

 Klassen und Ord., etc., 5 Bd., 11 Abt, 1902-1907. 



Fig. 722 



Peripatus eiseni 

 (Wheeler). 



