118 PROCEEDINGS OF THE NATIONAL MUSEUM vol. in 



Key to the genera of the subfamily Eurelinae 



1. Lower portion of the pleurotergites with a series of 6 to 10 sharp recurved 



spines on the caudal margin just above the legs; coUum of male with the 

 anterior margin set off by a distinct deep groove, and prolonged ventrad 

 into a rounded lobe extending below the level of the second tergite (fig. 5c) ; 

 apex of coxite of anterior gonopod with a fleshy membranous lobe (fig. 5a), 

 otherwise quite similar to that of Eurelus; coxal lobes of anterior legs well 



developed Centrelus Cook 



Lower portion of pleurotergites not produced into spiuules on the caudal 

 margin; coUum of male with anterior edge set off by a moderate groove and 

 not, or but slightly, produced ventrad as a rounded lobe; coxites of anterior 

 gonopods without trace of membranous lobes (figs. 4a, 6a) 2 



2. Sternite of anterior gonopods nearly straight across; tarsal claws of legs 4-7 



of males normal in size and shape; coxal lobes of these legs very small; 



ventral setae of legs 1-1-2-2-2-6 Comanchelus, new genus 



Sternite of anterior gonopods of male distinctly arched; tarsal claws of legs 

 4-7 of males reduced to tiny vestiges; coxal lobes of anterior legs very 

 largeandelaborated;ventralsetaeof legs 1-1-2-2-2-8. . . Eurelus Cook 



Genus Eurelus Cook 



Eurelus Cook, 1911, p. 161. 



Type species: Eurelus soleatus Cook, by origmal designation. 



Diagnosis: A genus of stout-bodied eurelines in which the anterior 

 tarsal claws of males are reduced to mere vestiges while the coxal 

 lobes are greatly enlarged. The caudal edges of the pleurotergites 

 are not provided with upturned spinules. 



Discussion: Although both the generic name and its only included 

 species were described at great length by Cook, he provided no 

 illustrations of the gonopods or other structm-es, and it is therefore 

 not surprising that Eurelus has become something of a pitfall to later 

 workers. The recent acquisition of material clearly referable to 

 E. soleatus makes it possible to clear up the mystery satisfactorily. 



Subsequent to Cook's 1911 paper, the first reference to the genus 

 appeared in an article on Texan millipeds by Chamberlin and Mulaik 

 (1941), in which two new names, lyroximus and kerrensis, were pro- 

 posed in Eurelus. Unfortunately these authors followed Cook's 

 precedent and presented no drawmgs of the new forms and thus 

 compounded the difficulties. Alost of their descriptions consisted 

 of comparisons with that of soleatus, and dealt only with very variable 

 structm-al details. Two years later (1943b), Chamberlin described 

 a third new form, Eurelus mulaiki, from New Mexico, We now 

 believe that proximus is a synonym of soleatus, that kerrensis belongs 

 to a different genus, and that mulaiki is for the present a sort of 

 species inquirendum. 



In 1949 Hoffman described, under the name ToUecolus parmnguis, 

 a specimen of what is almost certainly E. soleatus. Comparison was 

 made solely with the published descriptions of ToUecolus garcianus 



