Vol. XXVI, pp. 15-20 January 18, 1913 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 





A REVISION OF THE AMERICAN SPECIES OF 



PERIPATUS. 



BY AUSTIN HOBART CLARK. 





One of the most fascinating groups of existing organisms is 

 that commonly referred to under the somewhat general term 

 of " Peripatus." Not only do these animals offer most instruc- 

 tive data for morphological and phylogenetical speculation, but 

 they also possess a most absorbing interest for those who 

 inquire into the mj'steries of zoogeography, especially from the 

 pakeogeographical side. 



It is only within recent years that the knowledge of the vari- 

 ous forms included in Guilding's old genus Peripatus has been 

 brought to a point where it furnishes adequate data for the 

 zoogeographer. 



In the latest and most comprehensive work on the subject, 

 the well known and most excellent monograph by Professor 

 E. L. Bouvier (Annales des sciences naturelles, 9e serie, tome 

 2, p. 1-383, pi. I-XIII, nov. 1905-jan. 1906; tome 5, p. 61- 

 318, mars-juin 1907) the following classification for the fifty 

 recognized species is proposed: 



Family PERIPATID/E. 



Genera, Prripatus (divided into three sections, Andean forms, 12 species; 

 Caribbean forms, 17 species; African forms, 1 species); Eoperipalux 

 i \\ species). 



Family PKRIPATOPSID/E. 



Genera, Paraperipatus (1 species); Peripatopsis (6 species): Opisthopa- 

 tus (2 species); Peripatoides (4 species); Ooperipatus (4 species). 



Evans in 1901 grouped the five genera of the Peripatopsidae into three 

 subfamilies, Peripatoidime (Peripatoides, Ooperipatus and Opisthopatus), 



.-1'koc. Biol. So< . Wash., y>>\.. XXVI. 1913. (1.".) 



