Vol. XXXlJ ENTOMOLOGICAL NK\\> 3 



Pupa with body tapering to a blunt point at the posterior extremity, 

 which is provided with two short tubercles terminating in sharp spim -. 

 The head bears several stiff hairs; anterior and lateral margins of thorax 

 bear row of stiff hairs; dorsal surface of thoracic and abdominal segments 

 bears transverse row of stiff hairs; all hairs arising from tuberculate bases. 



An Undescribed Species of Ptychoptera from 



the Western United States 



(Ptychopteridae, Diptera). 



By CHARLES P. ALEXANDER, Urbana, Illinois. 



The undescribed species of the genus Ptychoptera Meigen 

 that is described herewith has been confused in collections 

 with the much larger and darker P. lenis O. S. 



Ptychoptera minor n. sp. 



<f Length, 9 mm.; wing, 8.6 mm. Rostrum and mouth-parts yellow; 

 palpi yellow, the last segment dark brown. Antennae with the basal 

 segment yellow, the second segment brown, the flagellum dark brown. 

 Head black, shiny. 



Pronotum yellow. Mesonotum black. Pleura black, gray pruinose, 

 the dorso-pleural membranes bright yellow. Halteres yellow. Legs with 

 the coxae yellow, marked on the outer face with purplish brown, the fore 

 coxae with a basal band and an apical spot, the middle coxae with a basal 

 and an apical band, the hind coxae with the outer face largely brown, 

 only the apical margin yellowish; trochanters light yellow; femora yellow, 

 the tips scarcely darkened; tibiae and metatarsi yellow, the tips darker; 

 tarsi brown. Wings with a strong yellowish gray suffusion, the costal 

 and subcostal cells and along vein Cu more yellowish; narrow, indistinct 

 brown seams along the cord and at the fork of R^+5- Venation: Sc 

 long, ending about opposite three-fourths the length of R4+S; Rx moder- 

 ately long, in alignment with R4+S, sometimes spurred at origin. 



Abdominal tergites black, segments three to nine with the lateral mar- 

 gins broadly reddish, this color increasing in amount on the terminal 

 segments, the hypopygium entirely reddish; sternites black, broadly 

 ringed caudally with yellowish. Male hypopygium with the ninth tergite 

 massive, deeply notched medially as in P. lenis but the lateral lobes only 

 moderately slender, their apices widely separated, quite far before tin- 

 tip on the ventral face with a small, blunt reddish lobe. IViiis-guard not 

 narrowed at the tip, the apex broadly rounded. 



In P. lenis the hypopygium is black, the lobes of the ninth tergite 

 slender, very narrowly separated at their apices, close belon- i he tip 



