158 



On the 8tli sternite the short median apical process is shorter and the 

 sides of the basal part in a straight line with each other, while in 

 basalis they gently recede from each other. 



Length 7 mm. ; wing 4.5 mm. 



Two 9 and one S Siskiyou Co., ("aliforiiia. June 2, 1911 

 (F. W. Xnnenmaeher) ; one S Santa ( 'rnz ^Mountains. Santa 

 Clara Co., Cal., April 25, 1913 (Bridwell). 



$ Type, allotype, and paratypes in the author's collection. 



Xamed in honor of F. W. Xnnenniacher, whose remark- 

 able ability as a collector has revealed many new and interest- 

 ing California and Arizona insects. 



"Whether the fact that the coastal mountains of California 

 where this species has been discovered were insular during 

 the Tertiaries has anything to do with its evolution from hasalis 

 remains to be elucidated. 



Hylaeus conspicuus (Metz). 



Corvallis, Oregon; Benicia, Berkeley, Santa Cruz Co., 

 San Gabriel Mountains, California (Bridwell). 



Hylaeus tridentulus (Cockerell). 



Mt. Jefferson, Oregon; Coast Mountains, Benton Co., 

 Ore. (Bridwell). Apparently a Transition species. 



Hylaeus varifrons (Cresson). 



Oregon: Crater Lake (O. H. Swezey), Three Sisters, Mt. 

 Jefferson (J. C. Bridwell). 



Xew Hampshire: Durham (J. C. Bridwell). Another 

 Transition species. 



Hylaeus episcopalis (Cockerell). 



I am convinced that at least three species of males are con- 

 fused in Metz' treatment of this species, but I am not yet pre- 

 pared to assign names for them on account of the involved 

 synonymy. 



