22 BULLETIN 46, UNITED STATES NATIONAL MUSEUM. 



** Posterior angles of 9, 11, 13 dorsal plates produced. 

 .. Ana] pair of feet armed with one spine; penultimate with two. 

 />. Coxae unarmed; coxal pores iu a single series. 



c. Antennae 20-jointed; prosternal teeth G; ocelli 25 Ho WEI, sp. nov., 9. 



cc. Antenna? more than 30-jointed; claw of the female genitalia tripartite. 

 d. Coxalpores round, 7, 7, 6, 5 ; antennae 31-jointed; ocelli 27. . AZTEC us, 10. 

 dd. Coxal pores transverse, 6, 6, 6, 4-9, 10, 9, 6; joints of antenna? 33-43; 



ocelli 23-48 FORFICATUS, 11. 



bb. Coxae armed with a single robust spine; coxal pores multiseriate; prosternal 



teeth 15-20 ; joints of antennae 20, long XANTI, 12 



. Anal and penultimate feet each armed with two spines; coxae unarmed; joints 



of the antennae 20 ; prosternal teeth 4 POLITUS, 13. 



* Posterior angles of the 7, 9, 11, 13 dorsal plates produced. 



a. Anal feet armed with one spine; coxae unarmed; coxal pores in a single series. 

 />. Penultimate pair of feet armed in the two spines; joints of antennae 31-38; 

 prosternal teeth 12-14 ; coxal pores 7, 7, 6, 5, 10, 10, 10, 9, trans- 

 verse; spines of the first pair of feet 2, 2, 1, 3, 3, 2. ..MORDAX, 14. 

 bl>. Penultimate pair of feet armed with three spines; joints of antennas 26-30; 

 prosterual teeth 8; coxal pores 4, 4, 5, 2, 4, 5, 5, 4, round; spines 



of the first pair of feet 1,3,2,2,3,2 CLARUS, 15. 



* Posterior angles of the 6, 7, 9, 11, 13 dorsal plates produced. 



a. Anal feet with a single spine; coxa?, armed; coxal pores multiseriate; joints of 

 antenna? 19-23; prosternal teeth 14-18; spines of the first pair of 

 feet 2, 3, 1-2, 3, 2 MULTIDENTATFS, 17. 



Subgenus ArcMlithobius Stuxberg. 



1. Lithobius kochii Stuxberg. 



Lithobius kochii Stuxberg, Ofver. Kongl. Vetens.-Akad. Fordhandl., 68, 1875 

 (Saiicelito, Cul.) 



To tliis species I refer a specimen from Ukiah, Gal., which has lost 

 the antennae and nearly all the feet. It has 11 ocelli, arranged in 5 

 series, prosternal teeth 4, small; coxal pores 3, 4, 4,3, small and round; 

 color fulvous. 



2. Lithobius minnesotae, sp. nov. 



Brown, head darkest, feet and ventral laminae not much paler; tip of 

 antenna 1 and prehensorial feet rufous. 



Slender, smooth ; very sparsely pilose. Head subcordate, wider than 

 long (3. 5: 3), smooth, very sparsely hirsute. 



Antennae short, joints 20, mostly long; the last long and sharp, 

 densely hirsute. 



Ocelli 13, arranged in series. 



Prosternal teeth 4, small and indistinct. 



Coxal pores 4, 5, 5, 4, rather small, round. 



Spines of the first pair of feet 1, 3, 2; penultimate 1, 3, 3, 1; last 

 pair 1, 3, 2, 1. 



Posterior pair of feet moderately long and slightly swollen. 



Claw of the female genitalia moderately wide, tripartite, the middle 

 lobe much longer; spines robust, subequal. 



Length of body 16"""; last pair of legs 5 111111 . 



Habitat. Fort Snelling, Minn. 



