310 THE CANADIAN ENTOMOLOGIST. 



Male antennae with large, nearly circular plates. Length, 4.25 mm.; 

 width, 1.4 mm. 



Head much deeper than in alternatus, nearly perpendicular down to 

 the antenna' in the female, sloping in the male ; venation as in alternatus. 

 Female segment slightly rounding posteriorly; pygofers long and slender, 

 exceeded by the ovipositor by two and one-half times its width. Male 

 antennae with large oval or nearly round discs, about twice as large as in 

 alternatus. 



Colour : vertex and face pale creamy, a pair of large round spots on 

 vertex ; face in the female irregularly mottled with rust brown or fuscous, 

 omitting a pair of circles around the spots on vertex, a pair of oblique 

 spots just outside the ocelli, and a broad stripe down the front. Male face 

 with a pair of crescentiform fuscous dashes outside the spots on vertex, a 

 pair of narrow brown lines down the front, a wider pair on the sutures, 

 and a still wider pair outside ; the outer pair and sometimes the middle 

 ones fuscous. Dorsal markings as in alternatus, usually somewhat 

 darker in the male. 



Described from twenty-four specimens from Alder, Fort Collinsj 

 Colo., and the mountains west of the latter place up to S.500 feet. 

 The small size, deep head and attenuate ovipositor readily separate 

 this from alternatus. The antennal plates alone will distinguish it 

 from verrucosus, to which in head characters and colour pattern it is 

 closely allied. 



Idiocerus obstinatus, n. sp. 



Resembling dolosus in form and colour, but smaller. Size of 

 verrucosus nearly, but with broader elytra. Length, 4.5 mm.; width, 

 1.5 mm. 



Vertex shortest in the middle ; face sloping, but slightly convex ; 

 elytra inclined to be flaring, narrowing before apex; outer anteapical cell 

 long and narrow. Male valve short and strongly trisinuate ; antennae 

 with a moderate-sized oval disc. 



Colour : vertex and face creamy yellow, a pair of very small round 

 spots on vertex, a pair of brown dashes outside of these, a median stripe 

 down face, fuscous in the middle and constricted above the ocelli, and a 

 pair of shining black stripes beneath the eyes ; pronotum washed with 

 very pale brown, a few irregular spots in front ; scu'tellum pale, with the 

 angles and a pair of spots on the disc brown ; elytra milky subhyaline, 

 the nervures heavily fuscous, omitting the base, the costal margins, 



