16 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.64 



large browTi area; scutellum pale brown, sparsely pruinose, with a 

 capillary brown median vitta; postnotum sparsely pruinose. 

 Pleura pale, sparsely pruinose. Halteres brown, the base of the 

 stem yellowish. Legs with the coxae yellow, sparsely pruinose; 

 trochanters obscure yellow; femora yellow, the tips narrowly infus- 

 cated; tibiae brownish yellow, the tips narrowly darkened; tarsi 

 brownish black, the bases of the metatarsi paler. Wings with a 

 brownish gray tinge the stigma darker brown, oval; a faint brown 

 spot at origin of Rs and an indistinct seam along the cord; whitish 

 obliterative areas before and beyond the stigma, and across the base 

 of cell 1st M^\ veins dark brown. Venation: Sc2 ending opposite 

 two-thirds of the length of the Rs; distal section of i?, entirely pre- 

 served; petiole of cell M^ about two-thirds the length of m: cell 1st M^ 

 elongate, the sides parallel; cell 2nd A narrow. 



Abdominal tergites obscure yellow, each tergite with the base dark 

 brown, sending caudad a median extension toward the posterior 

 margin; basal sternites dark brown apparently discolored; terminal 

 sternites yellow. Ovipositor with the tergal valves comparatively 

 short and compressed, the apices obtuse, the two valves forming a 

 V-shaped trough; sternal valves still shorter, very compressed. 



Described from a single female collected at Missoula, Montana, 

 July 6, 1917 (H. G. Dyar). 



Type.— Female, Cat. No. 26096, U.S.N.M. 



Tipida perexigua is the smallest Nearctic Tipnia and one of the 

 smallest Tipuline crane-flies so far made known. 



