JOHN B. SMITH. 261 



lowish scales. Secondaries white with a slight yellowish tinge in the 

 male, pale yellowish smoky in the female. Beneath whitish, with a 

 rather uniform sparse dark powdering. 

 Expand, 1.52-1.72 inches = 38-43 mm. 



Hab. — Glenwood Springs, Colorado, in August (Barnes); 

 Ft. Collins, Colorado (Gillette); Hot Springs, New Mexico, 

 7000 feet (Hulst). 



Two males and three females in good condition and all 

 very much alike except in size. The species has been con- 

 fused with caenis and gagafes, but more generally with the 

 former. It is duller and more powdery than either, the macu- 

 lation is barely traceable, there is hardly a trace of carneous 

 gray, and the primaries are a little more pointed. 



The joints of the male antennae are laterally produced into 

 very short branches, at the tip of which is a bristly process 

 set with finer, stiff hair. 



Euxoa biformata n. sp. 



Ground color rusty red-brown with a more or less marked smoky 

 suffusion. Head and thorax concolorous, palpi chocolate brown at 

 the sides. Primaries in the male with all the transverse maculation 

 practically lost in the smoky suffusion except for darker costal 

 marks. In the female all the maculation is distinctly traceable though 

 not well marked. Basal line marked by geminate spots on costa, else 

 obsolete. T. a. line geminate on costa, thence only the outer part 

 traceable ; nearly upright to internal vein, below which it makes a long 

 outcurve to margin. T. p. line geminate, very even, almost rigidly 

 parallel with outer margin ; inner portion very narrow, smoky, con- 

 tinuous ; outer a series of short blackish venular marks. A vague, 

 smoky, diffuse, irregular median shade through the outer portion of 

 median space. S. t. line irregular, marked only by the slightly darker 

 terminal space. In both sexes there is a series of very small dusky 

 terminal dots. In both sexes the claviform is wanting, and the ordi- 

 nary spots are obscure, barely traced out by a scant powdering of 

 yellow scales. Orbicular moderate in size, round. Reniform large, 

 kidney-shaped. Secondaries. smoky in both sexes, a little darker in 

 the female, veins smoky throughout. Beneath white, powdery along 

 costal region and toward apex. Legs dusky, tibiae rather conspicu- 

 ously pale-marked at tip. 



Expends, 1.55-1.80 inches = 39-45 mm. 



Hab. — Sierra Nevada, California. 



One male, the smaller, and one female, both in excellent 

 condition. The specimens contain no data as to their point 



TRANS. AM. ENT. SOC, XXXVI. NOVEMBER, 1910. 



