psilopus. 285 



at their tip ; the inner ones are sty liform, distinctly longer than 

 the outer ones and fringed upon their upper side with some few 

 minute light hairs ; the stile-like central organ is as long as the 

 inner appendages and is smoothly curved downwards. The coxae 

 and the long, very slender and very glabrous feet are yellowish. 

 The fore coxae of the % have a proportionally long, rather close 

 and delicate whitish pubescence ; in the 9 there are, instead of 

 the longer hairs, bristles of a white-yellowish coloring. The fore 

 femora of the % have upon the under side near the basis, three 

 thin yellowish bristles of decreasing length ; in the 9 there are in 

 their stead four stout yellowish bristles. The hind femora of the 

 % have upon the upper side near the basis a few long and very 

 delicate white hairs, which are not present in the 9 . The plain 

 and' slender fore tarsi are in both, sexes much longer than the 

 tibiae ; they are still much longer in the % than in the 9 ; the 

 first joint of all tarsi is very elongated, particularly in the % ; on 

 the fore tarsi it is about twice as long as the following joints taken 

 together, on the middle tarsi about three times as long, besides they 

 are distinguished by their slenderness, and apparently complete 

 glabrousness. The hind tarsi in both sexes are nearly as long as 

 the tibiae, their first joint in the % somewhat longer than the fol- 

 lowing joints taken together, but in the 9 somewhat shorter. 

 Tegulae on the margin with only a single quite small black dot; 

 their cilia whitish. Wings grayish hyaline, long and narrow, 

 towards the basis still more narrowed, particularly in the •% ; 

 their anterior veins are yellow, the posterior ones more infuscated ;' 

 the anterior branch of the third longitudinal vein is very long, 

 rather flat and but little curved; the posterior transverse vein is 

 far remote from the margin and has a very oblique position. The 

 % possesses, as a particular distinctive mark, upon the under side 

 of the basis of the wing, a crooked, black, rather stout thorn, in- 

 serted near the anterior margin. 



Hab. Pennsylvania. (Coll. Winth.) 



Observation. — The P. delicatus of Mr. Walker, who described 

 a 9 , has an entirely green abdomen, can therefore not be tener,- 

 as the basis of the abdomen of its 9 is always colored with yellow. 



