24 BULLETIN 46, UNITED STATES NATIONAL MUSEUM. 



peculiar knobs in both male and female; male, the end of the third 

 joints produced into a short, blunt lobe, which is surmounted with 4 

 spines, the basal third of the fourth joint jnoduced into a large, flat, 

 outward curving lobe, about 3 mm long, the end with a row of bristles, 

 tbe end of the same joint produced into a small, sharp, outward pointing 

 lobe; female, the end of third joint swollen, pilose, also two large spines, 

 base of fourth joint produced into a cylindrical lobe, directed forwards, 

 pilose, a little shorter than in the male, the end of the same joint swollen 

 on the inner side. 



Claw of the female genitalia wide, tripartite; spines stout, subequal. 



Length of body 10-15 mm ; last pair of legs 4-5 mm . 



Habitat. — Bloomington, Ind., and Bock Island, 111. 



The above description was taken from a male and female from the 

 former locality. I have also sent a male to the collection of Dr. Anton 

 Stuxberg, of Goteborg, Sweden, under the name of L. bilabiatus. Dr. 

 Wood, in his description of Lithobius bilabiatus, has included two 

 species. I have restricted bilabiatus to the one having the ordinary 

 type of hind legs ; the other I have described as a new species — Litho- 

 bius tuber. 



5. Lithobius proridens, sp. nov. 



Yellow-brown; antennae, feet, and ventral laminae pale. 



Slender, smooth, sparsely pilose ; ventral laminae more densely pilose 



isteriorly. 



Head obcordate, of about equal length and breadth (3: 2. 5), smooth, 

 -sparsely pilose. 



Antennae moderate, joints 24-29, short; rather densely pilose. 



Ocelli sometimes indistinct and irregular, 8-15, arranged in 4-6 series. 



Prosternal teeth 10-12, small, not crowded together. 



Coxal pores 3, 4, 4, 3-4, 6, 5, 5 large and round. 



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

 3, 3, 2; last pair 1, 3, 3, 1-1, 3, 3, 2. 



Posterior pair of feet long, not swollen. 



Claw of the female genitalia long and slender, whole; spines mod- 

 erate, subequal. 



Length of body 10-12 mm ; last pair of legs 4-5 mm . 



Habitat. — Bloomington, Ind. 



This species is common under leaves, etc. 



The following is the description of a specimen 5 mm long. 



Antennae short, joints 21. Prosternal teeth 10. 



Ocelli distinct, 1, 2, 1. Coxal pores, 1, 1, 1, 1. 



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

 1,3,3,1. 



6. Lithobius pullus, sp. nov. 



Brown; head darkest, feet and ventral laminae pale; tip of antennae 

 and prehensorial feet chestnut. 



