1887.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 627 



ib, Coxal i)ores in :i single series, traiisvcrHC. 



c. Peuultimato pair of legs armed with a single claw ; antenniu 150 to HS, jointed ; 

 Xirosterual teeth 6 +G or 7 -{-7 ; last two tarsal joints of anal legs dis- 

 tinctly or not sulcate mordax Kocii. 



cc. Penultimate pair of legs armed with a double claw. 

 d. Last two tarsal joints of anal legs sulcate on inner side, likewise the penult- 

 imate pair; antenmo ;>1 to 36, jointed ; prosternal teeth G -j- 6 to8-|-8; 



length of body 18 to ^G""» iyranicus Bollman. 



dd. Last two tarsal joints of anal and penultimate pairs of legs not sulcate; 

 anteumc 49 to 49, jointed ; prosternal teeth G + G to 11 + 11 ; length of 



body 20 to 37""" vorax Meineht. 



bbb, Coxal pores in several series; claws of penultimate pair of feet two; joints of 

 antennas 40 to 47 ; ocelli 13-4 to 2G-5 ; prosternal teeth 8 + 8 to 10 -f 10 ; 



claw of female genitalia not divided „ terreus Feduizzi. 



aa. Anal and penultimate pairs of legs each armed with two claws ; coxal pores in a 

 single series, round; coxa not armed beneath; antenn;e 31 or 32, 

 jointed; prosternal teeth 2 -j- 2; spines of lirst pair of feet 1, 1, 1. 



Juventiis Bollman. 



Ill the above key I have iut.roduced the European species, Lithohlns 

 terreus Fedrizzi; [ can not find any true specific characters to separate 

 Lithohius leptopus Latzel from it. 



Concerning' the geographical distribution of these species 1 may say 

 that transmariuus has been found in Louisiana, Arkansas, and Indian 

 Territory; clams in Florida; latzcli in Virginia and North Carolina; 

 mordax from Florida to Indian Territory, then north to Minnesota ; tyr- 

 aniens in Indiana; vorax from Mississippi to Indian Territory; and 

 juventus in Indiana and Tennessee. 



Indiana University, January 20, 1888. 



