Pipunculidae. 3 



wards, the labella are relatively very large. Thorax about quadratic, 

 a little arched above; prothorax is small, but it forms a long stalk 

 stretching into the head and carrying it; the stalk is long especially 

 in Pipunciiliis with its hollowed occiput; the propleural parts form 

 above a curious knob at eacli humerus; postscutellum is relatively 

 large; metathorax is very small and narrow and there is no chitinized 

 metasternum behind the hind coxæ; in Nephrocerus humeri and 

 scutellum are somewhat inflated. The thoracic disc is in Pipunculus 

 either nearly bare with only short and sparse hairs as dorsocentral 

 rows, or in some species it is more densely haired all over, and there 

 are no bristles; in the other genera it is more pilose, and among the 

 hairs some bristles or longer bristly hairs are discernible, as a rule 

 two posthumeral, a notopleural, a supraalar and two postalar bristles 

 and further a dorsocentral bristle behind, and the scutellum has here 

 at the margin about four to eight stronger hairs or bristles. Propleura 

 have in many species a vertical fan of distinct hairs; otherwise the 

 pleura are bare in Pipunculus, in the other genera mesopleura with 

 more or less dense longish hairs behind the suture (on pteropleura 

 Ost. Sack.); metapleura (Ost. Sack.) bare. Abdomen somewhat long 

 and narrow, longest in Nephrocerus, it is cylindrical, semicylindrical 

 or more flattened; in the male it consists in Pipunculus of five not 

 transformed tergites and four ventrites, the fifth being quite short, 

 in the other genera there are six normal tergites and five ventrites; 

 after these not transformed segments follow the more or less trans- 

 formed segments, constituting the exterior genitalia. The genitalia 

 are unsymmetrical, curving from left to right and bent in under the 

 venter; according to the above, the transformed segments are in 

 Pipunculus five, in the other genera four; in Pipunculus the sixth 

 segment is very short and hidden, only visible just at the left side and 

 sometimes a little above, while in the other genera it is visible and 

 normal, but small; the seventh segment is only present on the left 

 side, its tergite bends down on the ventral side, so that it occupies 

 the left half of the breadth of the abdomen both above and below, 

 while its ventrite accordingly gets a vertical position going from 

 the lower side of the tergite to the upper and thereby bordering the 

 left side of the ventral cavity, in which the hypopygium is laid up; 

 the eighth segment lies at the end and generally forms a roundish or 

 irregularly conical knob; it is curved quite over from the left to the 

 right and thus its morphological apical opening points forwards, and 

 lies beside the basal opening; the segment has in Pipunculus on its back- 



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