THE MYRIAPODA OF NORTH AMERICA 43 



14. Lithobius tyrannicus, sp. nov. 



Diagnosis. — Related to Lithobius latzeli Meinert, but the coxal pores 

 transverse; claw of female genitalia much longer and indistinctly tripar- 

 tite: size larger. 



Type. — IT. S. Nat. Museum. 



Habitat. — Greencastle, Bloomington, Salem, and New Providence, 

 Ind. 



Description of type. — Brown, more chestnut than L. latzeli; legs ful- 

 vous. Robust, rough, especially posteriorly; head wider than long 

 (0:5). Antennae moderately long, attenuate, joints 31 to 30, short. 

 Ocelli 32-7 to 45-9. Prosternal teeth + to 8 + 8. Coxa of anal legs 

 unarmed beneath, those of the 13, 14, 15 legs laterally armed. Spines 

 of first pair of legs 2, 2, 1; penultimate and anal pairs 1, 3, 3, 1 or 1,3* 

 3, 2. Coxal pores : $ , 0, 7, 7, 5 to 8, 8, 8, ; 9 , 7, 8, 8, 7 to 8, 9, 8, 7. 



Male : Femur, tibia, and first tarsal joints of anal legs silicate beneath, 

 last two tarsal joints sulcate on inner side, tibia depressed and sulcate 

 above; penultimate pair of legs the same, but tibia not flattened and 

 sulcate above. 



Female: Anal and penultimate pairs of legs similar to the penultimate 

 pair of male; claw of genitalia long and stout, indistinctly tripartite, 

 middle lobe much longer, inner smallest. 



Length of body 18.5 to 2G ,; m , width 2.5 to 3.8 mi " ; antennae 8 to 12"" n ; 

 anal legs 9 to 12" 1111 . 



I have compared this species with a series of X. latzeli from Chapel 

 Hill, N. C, and find in the latter the following differences worthy of 

 notice: Coxal pores S , 4, 5, 5, 4 to 6, 0, 0, 5; $ , 5, 5, 6, 5, to 5, 7, 0, 5; 

 of female genitalia rather short and wide, distinctly tripartite, middle 

 claw lobe somewhat the longest. 



Length of body 10 to 22""", width 1.8 to 2.G" 1 " 1 ; antennae 8 to ll mm 

 anal legs 7.8 to 10 m "V 



My description of Lithobius mordax, Proc. U. S. Nat. Mus. 202, 1887, 

 applies in part to this species. 



As several other species belonging to the subgenus Neolithobius have 

 been recently described, I have compiled the following analytical key 

 to help elucidate a few points as well as to correct some errors: 



ANALYSIS OF THE SPECIES OF NEOLITHOBIUS. 



a. Anal legs armed with a single claw, coxa 1 not armed beneath. 

 b. Coxal pores in a single series, round. 

 c. Penultimate pair of feet armed with a single claw ; antenna 1 30 to 40, jointed ; 

 prosternal teeth 5 + 5 or 6 + 6 ; last two tarsal joints of anal legs sul- 

 fate on inner side iransmarinvs KOCH. 



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

 <1. Prosternal teeth 4 + 4 or 5 + 5; autenme 2t> to 34, jointed; tarsal joints of 



anal legs not sulcate; orange or light chestnut clarus McNeill. 



dd. Prosternal teeth 6 + G to 8 + 8; antenna' 32 to 35, jointed; tarsal joints of 

 anal legs sulcate on inner side, brown latzeli Meinert. 



