18 ACADEMY OF NATURAL SCIENCES 



witli iuternal blackish clouds, and two impressed points in the 

 middle of the back ; feet paler, with a few hairs. 



Cabinet of the Academy. 



Less than one-fortieth of an inch. 



Inhabits Hirundo viridis, their nests and young. I am in- 

 debted for specimens to Mr. Reynall Coates. 



5. Gr. JULOIDES. — Body oval, pale brownish, depressed, be- 

 hind vesicular and whitish, the coriaceous epidermis of the ter- 

 2um terminating before the vesicular posterior margin in an emar- 

 ''inatiou ; feet short and very robust ; pulvilli dilated, very short. 



Cabinet of the Academy. 



I obtained several specimens from the body of Julus margi- 

 natus. 1 have also observed it on Polydesmus virginiensis. [73] 



Genus ORIBITA Lat. 



Body coriaceous, capitate or rostrated before, palpi and mandi- 

 bles concealed within the mouth ; feet terminated generally by 

 three nails, without pulvillus. 



1. 0. CONCENTRICA. — Black, opake ; tergum concentrically 

 lineated ; venter plain. 



Inhabits Pennsylvania. 



Cabinet of the Academy. 



Body spheroidal, black, opake, rounded before and carinated 

 behind, invested with a brown epidermis ; disk with about four 

 elevated concentric circles, connected by numerous interstitial 

 elevated lines ; posterior carina erenate in compliance with the 

 concentric lines ; head, subtriangular, rugose ; oral aperture oval, 

 closed by a valvular mentum ; eyes two, minute, brownish, ele- 

 vated on an elongated, slender filiform peduncle ; orbits elevated, 

 rather large, placed near the base of the head above ; feet rather 

 short, deep black, minutely granulated, terminated by three in- 

 curved nails J venter plain, granulated, valves of the cloaca some- 

 what lineated. 



A rather common insect, it moves very slowly, and inhabits 

 beneath the bark of trees. I have found it, most frequently, 

 beneath the bark of the common Carya (Nuttall) tomentosa. 



2. 0. OLABRATA. — Body glabrous, polished, globular-oval 

 black. 



Inhabits Georgia and East Florida. [74] 



[Vol. II. 



