30 BULLETIN 46, UNITED STATES NATIONAL MUSEUM. 



Yellow; slender. Joints of antennae 28. 

 Ocelli few, 13, arranged in 5 series. 

 Prosternal teeth 8. 

 Coxal pores 4, 4, 4, 3. 



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

 3, 3, 1. 



Length of body ll mui ; last pair of feet 4. 5" lm . 



16. Lithobius juventus, sp. nov. 



Brown; head and antennae dark, tip of latter fulvous, feet and ven- 

 tral plates pale. 



Slender, not smooth; sparsely pilose. 



Head large, subcircular, of nearly equal length and breadth, nearly 

 smooth ; sparsely pilose. 



Antennae moderately long, joints 31. short; rather densely pilose. 



Ocelli 10, arranged in 4 series. 



Prosternal teeth 4, small. 



Coxal pores 4, 4, 4, 3, round. 



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

 1, 3, 3, 1. 



Last pair of feet moderate, not swollen. 



Claw of the female genitalia wide, short, tripartite, middle lobe long- 

 est; spines long and slender, subequal. 



Length of body 9 mm ; last pair of legs 3.5 mm . 



Habitat. Bloomington, Ind. 



At first this species might be taken for the young of mordax. 1 have 

 no young specimens of the latter on hand, but judging from Dr. Mein- 

 ert's description of a specimen 15.5 nira long, it can easily be separated 

 by the number of prosternal teeth (4 instead of 10), by the spines of 

 the first pair of legs (1, 3, 2 instead of 2, 1, 1) and by the number of 

 ocelli. 



Subgeuus Eulitliobius Stuxberg. 



17. Lithobius multidentatus Newport. 



Lithobius multidentatus Newport, Trans. Liiin. Soc., xix, 365, 1845. 



Brown; varying from a deep mahogany to rather a light yellowish- 

 brown; ventral lamina and feet paler; tip of anteume, mouth parts, 

 and the last few joints of the hind legs rufous. 



Rather strongly or moderately robust; not smooth, more so poste- 

 riorly. 



Head subobcordate, wider than long (6:5), somewhat rough. 



Antenna short, joints 19-23, mostly long. 



Ocelli numerous, 27-35, arranged in 7-8 series. 



Prostemal teeth 14-18, rather short, stout, conic, not crowded to- 

 gether. 



Coxal pores numerous, large and small, arranged in 3-5 series. 



