231 



(luced beyond the apex of the narrow labrum, the palpi stout ; labium 

 not chitinized ; mandibles slender, with a long sharp apical tooth and 

 about 3 poorly defined teeth along the lower lateral margin. Loco- 

 motor organs consisting of rather broad fusiform areas on anterior 

 portion of abdominal segments except basal and apical; hairs along 

 margins of segmental incisions more distinct than elsewhere because 

 of their being slightly curved upward ; apical segment with 5 processes, 

 their structure and markings as in Figure 16, Plate XXXIV; anal 

 ventral blood-gills in the form of 4 short rounded protuberances. 



Pupa (PI. XXVIII, Fig. 15). — Length, 8-10 mm. Color as in 

 larva. 



Thoracic respiratory organs very little elevated, in the form of 

 longitudinal ridges very similar to those of some Tabanidae. Protho- 

 rax not so decidedly declivitous as in Helohia. A very long hair on 

 each side of thorax just above and slightly in front of base of wing; 

 front view of thorax and appendages as in Figure 15, Plate XXVIII. 

 Lateral margins of abdomen with long hairs situated upon slight eleva- 

 tions, as shown in figure last mentioned ; spiracles larger than in most 

 genera in the family, 6 pairs distinct; apical segments of male and 

 female as in Figures 16, 17, and 18, Plate XXVIII, 



The foregoing descriptions are made from specimens supplied 

 by J. A. Hyslop and taken at Wolfville, Md., May 20, 191 3. 



The larvae are found in wet mud along the banks of streams or 

 other bodies of water. The species is common in Illinois. 



Erioptera Meigen 



The larvae of two European species of this genus have been de- 

 scribed by Beling. He does not appear to have paid much attention 

 to the structure of the head of any larva that he described, the only 

 characters mentioned being those of general shape, armature, or 

 clothing of the body, the absence or presence of pseudopods, and the 

 shape of the apical segment. The species, judging from his descrip- 

 tion, differ from those of allied genera in having the thoracic segments 

 distinctly swollen and the body noticeably tapered posteriorly. The 

 apical segment is armed with 5 short processes as in Gnophomyia and 

 Helohia. 



The species described by Hart as Brioptera species (a) in his paper 

 on the Entomology of the Illinois River, is not an Brioptera accord- 

 ing to this generalization, but is, I think, much more closely related 

 to Gnophomyia than to BUiptera, contrary to Mik's opinion*. I figure 



*Wiener Ent. Zeit., Vol. 16, 1898, p. 62. 



