Pomona College Jothnal of Entomolooy 477 



BB. Claw of anal legs with (liNtinct bnsal spines; cc|)lmlic plate distinctly 

 and eonsideniMy overln|)ping the- first dorsal plate. 



Genus Sculopendra Linnaeus. 



Genus Hemiscolopendra Kracpelin 

 This genus is peculiar to the western hen)is|)here. Its species have for the 

 most part been considered under Scoloprndra, which they conform to in general 

 habit and structure. One species (//. punctivcntria Newport) is widespread in 

 the eastern United States, but none is known from California. 



Genus Arthrorhabdinus N'erhoeff 

 K.stablished as a subgenus to Arlhrorhahdus, a South African genus, for the 

 Texan species A. pygmaeus Poeock, a species which may possibly range across 

 .\rizona into southern ( allforiii.'i and wliieh is .-leeordingly ineluded here. 



Genus Scolopendra Linnaeus 



This, the typical centipede genus, ruibraees about two dozen valid species 

 and jjresents an excessive range under these of minor geographical forms, of 

 which a very large number have by different authors been dignified as species. 

 The variability in size, color, and many other characters is extreme. It is cosmo- 

 politan in the warmer zones of the earth. 



No basal plate present. Antennae composed of seventeen to thirty-one arti- 

 cles, of which the proximal four or more are glabrous. Prosternum with dental 

 ))l.itc; femur of prehensorial feet with basal tooth. Pseudojileura with toothed 

 or spined caudal process. A tarsal spine on each leg excepting last jiair. Prc- 

 femur of anal legs spined, always with spines at apical process or angle. 



The species occurring within California may be distinguished as follows: 



Key to Species of Scolopendra 



A. First dors.-il plate with a deep transverse impression back of anterior mar- 

 gin. 

 B. Cephalic plate inii)ressed with two fine longitudinal furrows which di- 

 verge ccphalad ; length 100 to 200 mm. S. lieros Girard. 

 BB. Cephalic plate wholly without furrows or at most with a weak median 

 furrow; first legs with two tarsal spines; length mostly from 50 to 

 100 mm. 

 C. A])ical i)roeess of prefeniur of anal legs mostly with four spines; cc- 

 ])h;ilie pl;ite always without any furrows. .S'. polymorpha Wood. 

 AA. First dors;il plate without a di-ep transverse impression back of cephalic 

 margin (legs of first p.iir with but one tarsal spine). 

 B. Prefemur of anal legs with none to five spines only. 

 C. Prefemur of anal legs without spines beneath and at most with two on 

 the inner or niesal surface. S. dehaani Brandt. 

 CO. Prefemur of .anal legs with four or five s|)ines, of which two are always 

 ventral in position. S. subspinipes Leach. 

 BB. Prefemur of an.'il legs with ten to fifteen spines, of which six to nine 

 are ventral in position and arranged in three series. 

 C. Apical process of prefeniur bearing three or four spines. 



S. morsitans Linnaeus. 



