OSTEN SACKEN.] 



ZOOLOGY UIPTERA. 565 



contiguous; no linear front being percei)tible between them. ^In Bl. 

 capitata, Lw.,^ , the upper half of the eyes is much smaller than the 

 lower one ; there is no long pile on the lower half; both halves are sepa- 

 rated by a distinct band, without facets ; the eyes are separated by a 

 narrow, linear front. Bl. capitata, Lw., the only American species hith- 

 erto known, was discovered by me in the woods, near Washiugton, D. C, 

 June 7-10, 18G2. In life, the upper half of the eyes was reddish-green, 

 the lower purple.) 



Ocelli in the usual position, on the vertex (they are proportionally 

 smaller than in Bl. capitata). 



Antennae short ; about equal in length to the longitudinal diameter 

 of the head, 15-jointed ; the second joint has more than double the 

 length of the first, and is curved ; the first joint of the flagellum is 

 subcylindrical ; the other joints are short, broader than long, and beset 

 with short pile ; the last joint is pointed. (In Bl. capitata, the antennae 

 are comparatively longer, being at least twice as long as the head ; the 

 second joint is not longer than the first ; the joints of the flagellum are 

 cylindrical, slender, which gives the antenna a filiform appearance. The 

 second joint of the antenna of BibiocepJiala resembles that of Apistomiay, 

 the blepharocerid from Corsica, as figured in Loew, loc. cit.^iig. 2.) 



Face, mouth, and palpi seem to be very like those of Blepharocera ; 

 about the latter two, it would be unsafe to judge from dry specimens 

 (About Bl. capitata, which I examined alive, I took at the time the fol- 

 lowing note: "The mouth of the female consists of several lancet-like, 

 horny organs, protected by a fleshy, movable under lip ; in tbe male, the 

 horny lancets are absent, or else iudistiuct. The last joint of the palpi 

 is elongate, slender." It is very probable that the mouth of Bibioce- 

 pJiala, $ , has a similar structure; only the last joint of the palpi seems to 

 be proportionally shorter.) 



Thorax rounded ; thoracic suture appears as a distinct, curved groove 

 on both sides, but is interrupted in the middle (similar to that of Bl. 

 capitata). 



Hypopygium large, projecting like that in a male Erax. (The forceps 

 seems to'be analogous in structure to that of ^/.. capitata ; only the two 

 principal i)rojecting pieces are broader, shorter, and bfld at the tip ) 



Feet long, strongly built, and bare, excepting a microscopic pubes- 

 cence; front and middle parts about equal in length, the last pair much 

 longer, especially through the great length of tlie femora. Front coxae 

 separated by a considerable space; the second joint of the trochanters 

 very long ; middle coxae more a])proximated; the hind ones contiguous. 



Front tibiae strongly arched, no distinct spurs at the end; middle and 

 hind tibiae straight ; the middle ones with two stout, but very small 

 spurs, the hind ones with two short, stout, and very distinct spurs at 

 the end. The joints of the tarsi on all the feet gradually diminish in 

 length, the first being by far the longest; the last joint, however, is 

 nearly twice as long as the preceding one. Ungues elongated, strong at 

 the basis; their underside, under a magnifying-power of 80-100, shows 

 a dense brush of exceedingly minute, erect hairs, which extends to about 

 half of the under side on the first pair, and to about three-quarters on 

 the two others. The bnsis of the ungues shows some longer bristles. 

 No distinct empodia. (The curved frout tibiae seem to indicate a habit 

 of throwing the front feet backward and claspiug the thorax with them; 

 at least some of the dried specimens were in that position In Bl. capi- 

 tata the feet are comparatively longer and more slender; the front tibiae 

 are straight; the last tarsal joint is not longer than the preceding; the 

 middle coxae are contiguous, e&.) 



