157 



regard to sculpture he has fallen into some errors in his account 

 of the species. Crawford has pointed out (Can. Ent. 45 :154- 

 156, 1913) his error in sinking Hylaeus mesillae (Ccx^ker- 

 ell) as a variety of the widely distributed H. Cressmii (Cock- 

 erell). I wish here to make some additional notes and com- 

 ments. 



Hylaeus basalis (Smith). 



This is a species of the Boreal and Transition zones and 

 seems to be confined to them. All the specimens I have takcni 

 have been from the mountains in California and Oregon. Metz 

 sneaks of it as not restricted in its destribution. My localities 

 for it are Oregon : Cascade Mountains, — Detroit, Mt. Jefferson, 

 Three Sisters; Coast Mountains — Benton Co. (J. C. Bridwell). 

 California: Siskiyou Mountains (F. W. Xunenmacher), San 

 Jacinto Mountains (Bridwell). 



Hylaeus Nunenmacheri n. sp. 



The well-marked Hylaeus hasalis (Smith) has hitherto 

 remained rather isolated. Metz' //. potens only known in 

 the male sex has genital characters similar but is quite differ- 

 ent externally from basalis. It was with interest that I have 

 discovered mixed with my material of basalis a very siuiilar 

 but smaller species. 



$ Clypeus a little broader in proportion more sparsely punctured, the 

 punctures less oblique, the surface less lineolate, particularly apically ; 

 sculpture of basal area feebler and its integument more shining. The 

 rugae are confined to a few short weak longitudinal ridges along the 

 anterior margin while there are some reticulations in basalis. In both 

 species the integument of the area behind the rugosities is microscopi- 

 cally tessellate but it is shining as seen with a hand lens in Xuiicii- 

 macheri, opaque in basalis, due to the greater impression of the lines 

 bounding the tessellations in the latter. 

 Length 7 mm. ; wing 5.5 mm. 



$ Clypeus shorter and broader than in basalis. The integument of 

 the area duller than in the $ but the rugae similar. 



Seventh sternite with the lateral lobes more transverse than in basalis 

 the sinus between them less profound, their posterior margin brace shaped 

 ^ » ' . while in basalis the posterior sinus is profoundly V-shaped 



and the sides are rounded off toward the base. 



