OF WASHINGTON. 29 



To these moist spots came flies in large numbers, apparently 

 two species, one of which was large, 6 mm, in length, yellow- 

 ish, covered with long yellowish hairs, and greatly resembling 

 Scatophaga fur cat a in general appearance. The other was 

 much smaller, black, shiny, with a distinct dark spot near the 

 tip of the wing. The large woolly one appeared very aggres- 

 sive, alighting often upon the black, shiny one and with his 

 woolly legs outspread so as to hide his captive completely he 

 would run about over the moist wood as if he were a single 

 specimen. But at last I saw a very small woolly specimen 

 alight upon a large black shiny one and in this case saw copu- 

 lation take place. Then the true state of affairs dawned on 

 me. 



I collected a series of about 39 males and 12 females, and 

 3 pairs in copula. In this series there is enough variation 

 among the males (in size, pubescence, length, and color of 

 scutellum) to make half a dozen modern species, but the 

 females appear to be much alike. The males vary in size from 

 a 6^ millimeter specimen, which was covering a 4 millimeter 

 female, to a 2^ millimeter specimen caught in copula with a 

 3^ millimeter female. The scutellum in large males is much 

 elongate and yellow, while in small ones it is short and black, 

 and there is an almost complete series of intergrades between 

 these extremes. 



Mr. Coquillett has recently published^ the description of a 

 new genus and species, Omomyia hirsiita, made from 8 speci- 

 mens collected at Lancaster, Cal., by Mr. A. Koebele, in April, 

 several years ago. One of these cotypes is labeled " Yucca 

 hrevifolia." They are all large males, and only the large males 

 in my series agree with the generic description. Through an 

 oversight my series of over 50 specimens was not before Mr. 

 Coquillett at the time his description was drawn up, but he 

 tells me that he intends to publish in the Canadian Entomolo- 

 gist a generic diagnosis revised so as to include the females 

 and depauperated males. 



— Mr. Banks made some remarks upon a collection of in- 

 sects which he had made in a locality in the open woods near 

 Falls Church, Va, This collection showed a remarkable asso- 

 ciation of insects of varied forms and habits. In the discus- 

 sion Mr. Schwarz made a strong plea for the collection of 

 such associations, citing the interesting work of Hubbard and 

 several others. 



* Canadian Entomologist, 1907, p. 76. 



