296 DIPTERA OF NORTH AMERICA. [PART IV. 



Sumatra. About Cylindr. ornatissima Doleschall, from Amboina 

 (1. c. Yol. XYII, p. 80), I have no opinion, and I may say the 

 same about Cylindr. hyaloptera Philippi, from Chile (Verh. 

 Zool. Bot. Oes. in Wien, 1865, p. 614). The descriptions of both 

 species are too short to enable me to judge whether these species 

 are really Cylindr otomae or not. 



Gen. XLI. CYiiOTDRQTOMA. 



First longitudinal vein incurved at the tip towards the second and end- 

 ing in it (and not in the costa) ; a marginal, a submarginal, a discal, and 

 Jive posterior cells. 1 Antenna 16-jointed, joints sub cylindrical, elongated ; 

 first joint short, not longer than the second. Eyes hare, separated by a 

 rather broad interval above and below the head. Tibiae with distinct spurs 

 at the tip. Empodia distinct. Forceps of the male with claw-shaped 

 horny appendages, which, in the state of repose, are folded backwards, 

 like the blade of a penknife, towards the upper side of their basal pieces ; 

 a long, narrow, linear lamella, deeply tridentate at the tip, protrudes when 

 the forceps is opened. Coloring yellow, with black stripes and spots. 



Head rather broad posteriorly. Proboscis very short; palpi 

 somewhat elongated, last joint elongated ; in C. americana it is 

 about equal in length to the two preceding joints taken together. 

 The antennae of the male with elongated, almost cylindrical joints ; 

 finely pubescent, with short, thin, rather scattered verticils ; those 

 of the female shorter, less pubescent. In both sexes, the first 

 joint is remarkable for its shortness. Collare moderately de- 

 veloped. Thorax short, stout. Feet slender; spurs at the tip 

 of the tibia3 of moderate length ; fore coxae short ; empodia dis- 

 tinct ; excision at the basis of the last tarsal joint of the male, on 

 the under side, rather small, and this joint not particularly 

 modified. Abdomen long, slender, conspicuously club-shaped at 

 the tip, in the male ; the long, narrow, linear, horny lamella, which 

 usually protrudes when the living insect opens its forceps, ends 

 in three sharp points. The ovipositor of the female of C. dis- 

 tinctissima has a very peculiar structure. It is rather large ; the 

 upper valves are lamelliform towards the tip, and the lower ones 

 are curved in such a manner as to leave a considerable empty 

 space between them and the upper ones. Although I have not 

 seen the female of C. americana, I have no doubt, from its close 



1 Four in Cyl. nodicornis 0. S. ; it will be explained below, that this 

 generic character applies only to the typical species, C. distinctissima and 

 americana. 



