NO. 1938. THE DIPTEROUS FAMILY PHORID^—MALLOCH. 497 



slightly shining, abdomen dull black with scattered hairs in both 

 sexes and the segments subequal, no noticeably longer or shorter 

 segments in either sex, except, as is usual, the sixth in male which 

 is slightly elongate, the hypopygium of male with several strong 

 bristles on lateral angles and a few on the sides, anal protuberance 

 stout and rather short; legs dusky yellow, especially the dorsal and 

 ventral surfaces of hind femora, hind tibiae with a dorsal ridge which 

 divides at about apical third to inclose a flattened surface which 

 extends to apex in male, the female has an indication of a flattening 

 at same part, but it is not so distinct as to be very noticeable, and 

 unless the sexes are associated it is difficult to distinguish the female 

 from agarici and its allies; wings clear, costa to short of middle in 

 male, to near middle or to middle in female, first division fully t^vice 

 as long as second, third half as long as second in both sexes, fringe 

 long, fourth vein slightly bent at base andshghtl}'' recurved at margin 

 of wing; halteres yellow. 



Length, 1^-2 mm. 



A very large number of specimens belonging to this species have 

 been reared from fungi in connection with the i\Iushroom Investiga- 

 tion, under the Bureau of Entomology. The locahties are the Dis- 

 trict of Columbia, from Agaricus campestris (Popenoe), and from 

 Coprinus comatus (Wall) a pair on windows in museum May 17, 1912 

 (Knab and Malloch) and Sandusky, Ohio, from Agaricus campestris 

 (Vaihmeyer). Specimens in collection marked "fi-om mushrooms," 

 District of Columbia, 1902, and New Jersey, 1895. The fact that 

 these specimens were reared from Agaricus led me to suppose that 

 this was identical with the next species, but Mr. Brues informs me 

 that his species differs in the characters mentioned in table as to the 

 abdominal bristling, and that ''the hind tibiae are also more swollen, 

 and the peculiar cut-oft' part extends farther toward the outer edge" 

 (antero-dorsal surface?). He however makes no mention of the 

 costal lengths in the two species when he compared his with the speci- 

 mens sent by Wood, though I have included it in my table. This is 

 the same as the species described by Wood as derasa,^ It was described 

 originally by Felt from the female and an examination of some of 

 Prof. C. W. Johnson's cotypes proves it to belong to this male. 

 There was at least one male among the cotypes which I examined. 



APHIOCHiETA SMITHH Brues. 



Male. — Black, frons shghtly poUinose, suture and ocellar tubercule 

 present, only two distinct post-antennal bristles, outer pair of bris- 

 tles in fi.rst row very low down, near the anterior lateral angle of 

 frons, outer bristles in second row very near to eye-margin; third 



» Ent. Mo., May, 1909. 

 48702°— ProcN.M. vol.43— 12 32 



