146 MISCELLANEOUS STUDIES 



4] . Genus Prociphilus Koch 



Koch, Die Pflanzenlause, p. 279, 1857. Type Aphis bumeliae Schrank. 

 KEY TO CALIFORNIAN SPECIES 



1. Stigma of forewings conspicuously darkened. V with a few annular secondary 

 sensoria, VI with or without any. Dorsal thoracic wax plates small and 



oval alnlfoliae (Williams) 



Stigma not conspicuously darkened. V and VI without annular secondary 

 sensoria. Dorsal thoracic wax plates quite large and triangular. 



venafuscus Patch 



170. Prociphilus alnifoliae (Williams) 



Williams, Univ. Neb. Studies, vol. 10, p. 91, 1910. Pemphigus (orig. desc.). 

 Baker, Jour. Agr. Ees., vol. 5, p. 1118, 1916 (note). 



Records. Heteromeles arbutifoliae ; Sespe, Ventura County, March, 1915 (S. 

 H. Essig); May, 1915 (C. P. Clausen). 



There has been no record of this species from California heretofore, 

 but the author has specimens taken on California holly or Christmas 

 berry in Sespe Canyon during March and May, 1915, by S. H. Essig 

 and C. P. Clausen. 



171. Prociphilus venafuscus Patch 



Patch, Ent News, vol. 20, p. 319, 1909. Pemphigus (orig. desc.). 



Essig, Pom. Jour. Ent., vol. 3, p. 553, 1911. Pemphigus fraxini-dipetalae 

 n.sp. (orig. desc.). 



Essig, Pom. Jour. Ent., vol. 4, p. 699, 1912. Pemphigus fraxini-dipetalae 

 Essig (list). 



Childs, Mon. Bull. Cal. Comm. Hort., vol. 3, p. 220, 1914. Pemphigus 

 fraxini-dipetalae Essig (list). 



Wilson, Trans. Am. Ent. Soc., vol. 41, p. 85, 1915. Prociphilus fraxini- 

 dipetalae (Essig) (note). 



Davidson, Jour. Econ. Ent., vol. 8, p. 421, 1915. Prociphilus fraxini- 

 dipetalae (Essig) (list). 



Baker, Jour. Agr. Kes., vol. 6, pp. 1118-1119, 1916 (desc. notes, synonymy). 



Records. Fraxinus dipetala; Santa Paula (Essig), Contra Costa and Santa 

 Clara counties (Davidson): F. oregona; Oregon (Wilson); Berkeley, April, 1915: 

 Aesoulus calif or nicus ; Sacramento (Childs): Pseudotsuga taxifolia; Oregon (Wil- 

 son). 



Occasionally this very large aphid is found infesting the leaves 

 of ash in the San Francisco Bay region and in the mountains of 

 southern California. In early summer it leaves the ash, and according 

 to Wilson infests the roots of Douglas fir in Oregon. At one time 

 Leroy Childs found a few specimens on buckeye in the vicinity of 

 Sacramento, but it is probable that these were accidental there. 



