Mar., 1909.J ROHWER : CrYTOCAMPUS IN BOREAL NORTH AMERICA. 17 



deeply, subangularly emarginate ; lobes broad, rounded obtusely at apex. Antennal 

 foveae very large, extending much above the antennae. Middle fovea elongate, deep, 

 open at the top. Ocellar basin not as large, and better defined than in 9 ; no furrow 

 from lower ocellus. Lateral ocellar furrow stronger in some specimens than in others. 

 Third and fourth antennal joints equal ; apical joint tapering, shorter, or occasionally as 

 long as the preceding joint. Sculpture of head and thorax as in 9 • Inner tooth of 

 claws shorter than in 9- Venation as in 9- Procidentia rounded at tip, quite 

 prominent. Hypopygium rounded at the tip. Black : head below the antennae, 

 inner orbits sometimes, posterior and superior orbits broadly, pronotum, tegulae, legs 

 except extreme bases of coxae, venter of abdomen (sometimes dusky basally) bright 

 rufo-ferriiginoiis. Apical three or four joints of antennae ferruginous. Wings hya- 

 line, iridescent ; venation pale brown, basal half of stigma and basal part of costa 

 pallid to white. 



Habitat. — Boulder, Colorado. Many males and females bred 

 from galls on Salix luteosericea Rydb. Hatching in laboratory April 

 12-18, 1907. Two males on foliage of Salix luteosericea May 12, 

 1907 (S. A. Rohwer). Many males bred by G. P. Weldon from 

 galls collected near Ft. Collins, Colorado. Mr. Weldon gives his 

 Salix as S. longifolia. According to Dr. Rydberg (Bull. 100 of Colo. 

 Ag. Exp. Sta.) longifolia does not occur in Colorado, while luteosericea 

 is common in northern Colorado and has been taken at Ft. Collins. 

 It is undoubtedly Salix luteosericea from which Mr. Weldon collected 

 his galls. 



Gall a gradual enlargement of the twig, about 30 mm. long and 

 from 7 to 10 mm. in width. Color that of the twig. Not roughened 

 beyond the character of the dry bark. The small galls contain but 

 one chamber while the larger ones have two larvae, each in a separate 

 chamber, each chamber having a separate opening. Galls may be 

 found with three larvse, but all those I examined had either one or 

 two. On Salix luteosericea Rydb. 



Larva, about time of maturity, about 5 mm. long, of a creamy 

 white color, with a black or dark head. 



Fupa a few days before the adult emerges is about 5 mm. long 

 (Mr. Weldon found some which were 6 mm.). For some time after 

 the larval stage the pupa is the same color as the larva, but as the time 

 of hatching approaches it becomes darker. The length of the pupal 

 stage is rather short, in some cases being about two weeks. 



In the laboratory the males appeared about the same time as the 

 females, but in the field I found no females until after the males had 

 been out two or three days. However, they may both emerge about 

 the same time, as it is quite possible that I might overlook the female. 



