psilopus. 273 



tarsi yellow ; the spur of the middle tibiae very short ; the first joint of 

 the middle tarsi plain. 

 9 Long. corp. 0.15. Long. al. 0.15. 



Syn. Psilopus inermis Loew, Neue Beitr. VIII, 93, 11. 



This species is likewise most closely allied to the £ of P. 

 scobinator. In the coloring there are no differences, except that 

 in P. inermis the hind tibiae are somewhat infuscated at the very 

 extreme tip, while in the g of scobinator the blackish-brown 

 coloring is extended nearly over the whole of their last quarter, 

 and that in inermis the first joint of the middle tarsi is brownish- 

 yellow nearly to the middle. Whether these differences in the 

 coloring are constant, further observations must show. The plas- 

 tic differences, which secure the specific distinctness of inermis 

 from the two previous species lies in the structure of the middle 

 feet. "Whilst in the latter that bristle, which is inserted near the 

 tip of the tibiae upon the inner side, forms an unusually long, 

 diverging spur, and much exceeds in length the bristle inserted 

 on the front side of the tip, in P. inermis the bristle inserted on 

 the inner side is not only the much smaller one, but is also not 

 diverging ; the remaining bristles of the middle tibiae are consider- 

 ably longer than in scobinator and calcaratus ; the first joint of 

 the middle tarsi is plain, as in calcaratus, but has upon its under 

 side a still smaller number of very short, straight bristles ; the fore 

 and middle tarsi are somewhat longer than in the two previous 

 species, still this difference is but trifling. 



Hab. Pennsylvania. (Osten-Sacken.) 



II. TegulvE with pale cilia. 

 A. Antennae entirely black. 



15. P. scintillans Loew. % and J .— Totus nitidissimus, viridis 

 vel ex viridi chalybeus, abdomine interdum ex aureo viridi, antennis 

 nigris, coxis anticis pedibusque flavis. 



% . Alarum costa breviter ciliata, hypopygii appendicibus atris. 



9 . Alarum costa non ciliata. 



Very shining, green or bluish-green, abdomen sometimes golden-green; 



antennae black ; fore coxae and all the feet yellow. 

 % . Costa with short cilia ; appendages of the hypopygium black. 

 J. Costa not ciliated. Long. corp. 0.14—0.16. Long. al. 0.15 — 0.17. 



Syn. Psilopus scintillans Loew, Neue Beitr. VIII, 94, 13. 

 18 



