NO. I DISTRIBUTION OF THE ONYCHOPHORA — CLARK 13 



closely to the Malayan on account of a greater similarity of the condi- 

 tions under which it was perfected. 



In the Malayan region, subsequent to the separation from Africa, 

 evolution gradually produced, through the processes which have al- 

 ready been given in detail, a more specialized type, Eoperipatus, 

 which represents the dominant type under present conditions. It is 

 possible that this represents the only type in the region, for it is the 

 only type we know ; but it is probable that subordinate types will 

 eventually be discovered. 1 



THE DISTRIBUTION OF THE AMERICAN SPECIES OF THE 

 PERIPATID^E 



The details of the distribution of the American species of the Peri- 

 patidas deserve special consideration. In South and Central America 

 we find the very primitive Oroperipatus almost entirely confined to 

 the territory west of the watershed of the Andes, only three species 

 {Oroperipatus bimbergi, 0. multipodes and O. eiseni) occurring in 

 the mountainous regions east of the divide, while the remaining 

 territory, including the West India islands, is occupied by the less 

 primitive Peripatus, two species of which, in Colombia and Panama, 

 have gained a foothold in the area otherwise occupied solely by 

 Oroperipatus. 



While the species of Oroperipatus exhibit great uniformity, this 

 is not by any means true of the species of Peripatus, which fall into 

 four well marked subgenera; one of these subgenera (Plicato- 

 peripatus) is, so far as we know, confined to the island of Jamaica ; 

 another (Macro peripatus) occurs from Rio de Janeiro northward to 

 Vera. Cruz, including the island of Trinidad ; the third (Epiperi- 

 patus), with almost the same continental range, though not known 

 either so far north or so far south, extends to Trinidad, Tobago, and 

 Grenada ; while the fourth (Peripatus) , found in a small area be- 

 tween Caracas and La Guayra and Merida in Venezuela, near Bogota 

 in Colombia, in northern Panama, and in Costa Rica, is eminently 

 characteristic of the Antillean region, being found on Jamaica, Haiti, 

 and Puerto Rico, and on the Lesser Antilles from St. Thomas to and 

 including St. Vincent. 



It is worthy of especial mention that, whereas Oroperipatus, the 

 most primitive type, is chiefly developed in, and very largely con- 

 fined to, the cool regions of the high mountains, where very uniform 



1 Since this was written the related genus Typhloperipatus has been described 

 from the adjacent portion of Tibet. 



