1902.] NATURAL SCIENCES OF PHILADELPHIA. 43 



more or less converging anteriorly or parallel, not raised into rngse; 

 ferruginous, the head and the last dorsal and ventral plates usually 

 darker, coloration of head deeper immediately caudad to the frontal 

 suture. Antennre rather short, pilose; articles 20-23, large, de- 

 creasing in size from first to last. Ocelli on each side in an oblong 

 to narrowly oval patch, 16-25 in number, arranged in 3-5 longi- 

 tudinal series. Prosternal teeth 7-7 to 9-9, black, uniform. 

 Spines of first legs 2, 3, 2, of penult 1, 3, 3, 1 with 2 claws, of 

 anal 1, 3, 2, 1 with the claw single; coxse of the last two pairs of 

 legs armed beneath and also laterally with a stout spine. Coxal 

 pores usually of several sizes, numerous (often 25 and over), 

 arranged in 2-4 series. Claw of genital forceps of female tripartite, 

 the middle lobe a little longest, the lateral subequal, all short and 

 blunt ; basal spines 2-2, moderately stout, the outer pair longer and 

 stouter than the inner. 



Length 19-27 mm. ; width 2-3 mm; length of anal legs 8-11 

 mm. ; length of antenna; 8-11.5 mm. 



Juvenis. — Specimens 13-15 mm. long measure 1.5 mm. in width; 

 length of anal legs 4.5 mm. ; length of antennae 5 mm. Color 

 brown. Ocelli 10-15 in 2—3 series. Prosternal teeth 5-5 to 7-7. 

 Spines of the first and penult pairs of legs normal , those of the anal 

 pair normal or'l, 3, 2, 0. Coxal pores 6-12 in 2-3 series. 



Habitat. — Along the middle and lower courses of canyon streams 

 throughout the greater extent of the Wahsatch Mountains, Utah. 



Etymology. — l^o^im. pervmndus, very elegant. 



5. Lithobius multidentatus Newport. 



LitJioUus multidentatus Newport (1845); id. Gervais (1847). 

 Bothropolys nohilis Wood (1863). 

 Bothropolys multidentatus Wood (1865). 

 Lithobius multidentatus Stuxberg (1877). 



Habitat. — Eastern United States, south from Missouri, Illinois 

 Michigan and Pennsylvania {seq. Wood, Bollman et al.). 



