1919.J NATURAL SCIENCES OF PHILADELPHIA. 193 



and middle and hind tarsi are wliite; the latter not at all darkened 

 apicall}^ The fore tibiae may be darkened at bases and the middle 

 tibise may be light brown. The basal segment of ovipositor is very 

 large, about one-half as long as the abdomen and as broad as long. 

 The first posterior cell is broader at apex than at base, almost twice 

 as broad; anal cell truncate, not acute. In other respects similar to 

 pibrans. 



Type. — 9 ; Sw^arthmore, Delaware County, Pennsylvania, May 25, 

 1912, (E. T. Cresson, Jr.), [A. N. S. P. No. 6210]. A series of Id', 

 3 9 , from Ithaca, New York, May to June, [Cornell] are conspecific. 



That this species may not be congeneric with vibrans is possible, 

 but I am unable to place it in any other genus. The fact that Sieop- 

 tera is not a typical Ulidiinse, especially in the construction of the 

 anal cell, allows one to enlarge somewhat on its limits. The present 

 species will no doubt be found in many collections under colon or 

 vibrans. 



PSILIDiE. 

 Psila angustata new species. 



Similar to lateralis Lw., but larger and the third antennal jdint is 

 much longer. In lateralis the size is 3.5-3.-9 mm., and the third 

 antennal joint is scarcely longer than the second. TaxMiy to yellow; 

 third antennal joint apically, occiput spot, face medianly, faint 

 spot behind vetrical bristles, pleural stripe under humeri to base of 

 halteres, and entire abdomen, black. Lower part of plem'a, cpxae, 

 and legs, pale yellow. Wings hyaline, yellowish to browmish along 

 costa and veins. Arista white pubescent. Third antennal joint 

 slender, three times as long as second. Length, 4.7-5.9 mm. 



Type.— d; Ithaca, New York, August 23, 190'4, [Cornell Univer- 

 sitj']. Paratypes. — 3d, 5 9 ; topotypical. 



PIOPHILID^. 

 Mycetaulus hornigi new species. 



Agreeing with the generic description of Mycetaulus, but super- 

 ficially simulating Piophila nigriceps Meig. The two dorsocentral 

 bristles each ■s\'ith a stout setula before it, but behind the suture, 

 and are readily distinguished from the short abundant pile. Fore 

 femora vnih. 3-4 flexor bristles at apical end of the posterior flexor 

 series of hairs. 



d. Black, polished. Occiput subopaque but not polished. Pro- 

 pleura with silvery dot. Second antennal joint, base of third, base 



