896 CHARLES PAUL ALEXANDER 



insects resemble tiny species of the genus Limnophila. The adult flies 

 are not uncommon on rank herbage, especially ferns, in woods and usually 

 near running water. As already stated, the immature stages have not 

 been reared, but larvae found by the writer in Maine are referred with 

 considerable confidence to Adelphomyia americana and A. cayuga, while 

 larvae and pupae of another species taken at Ithaca, New York, seem to 

 be those of A. minuta. The larvae show a curious combination of tribal 

 characters. The general appearance and the structure of the spiracular 

 disk are altogether those of one of the Hexatomini; but the head capsule 

 and the details of the mouth parts indicate a relationship with the Pedi- 

 ciini that cannot be denied. 



Adelphomyia minuta Alex, (supposition) 



1911 Adelphomyia minuta Alex. Can. Ent., vol. 43, p. 287-288. 



Adelphomyia minuta is a characteristic late spring species, common in 

 boggy woods and on vegetation along rapid streams. Larvae and pupae 

 which are referred to this species were sifted from organic mud taken on 

 Bool's hillside, Ithaca, New York, thruout May and early June, 1917. 

 The pupae referred to this species strongly resemble those of Dicrano- 

 phragma but in reality are very different. The species is discussed 

 herewith in the hope that it may be definitely recognized in the future. 



Larva. Length, 4.5-5 mm. ; caudal fringe, 2 mm. additional. 

 Diameter, 0.4 mm. 



Coloration, saturated yellow with a faint orange-brown tinge. 



Form narrow, body tapering gradually to both ends, spiracular disk narrowed. Body 

 clothed with a delicate appressed pubescence and numerous tufts of conspicuous stiff hairs 

 which produce a spiny or bristly appearance; the more conspicuous of these tufts located on 

 pleural region, there being three such rows on abdominal segments one on basal ring, the 

 second and largest at base of posterior ring, and the third just before posterior margin of 

 segment and more ventral in position; only the large intermediate tuft present on thoracic 

 segments, the small brush on anterior annulus of abdominal segments lacking. Spiracular 

 disk (Plate LIX, 305) with four lobes; ventral pair not more than three times length of lateral 

 pair; inner face of lobes margined with brown; at tip of ventral lobes a fringe of exceedingly 

 elongate hairs, which are from one-third to nearly one-half length of entire body and about 

 fifteen times length of lobes bearing them; a stiff sensory bristle located in black margin 

 at tip of lobe; lateral lobes with fringe of hairs relatively much shorter, tho still long. 

 Spiracles large, close together, separated by a distance less than diameter of one, the middle 

 piece black, the ring pale yellow. Anal gills four, slender, hyaline, each subdivided by con- 

 strictions into four lobes which are gradually narrowed from the base outward, the last being 

 cylindrical. 



