330 



University of California Puhlications [Entomology 



wild blackberry. E. vitifolius C. & S., Berkeley, California. 

 March 25, and June 6, 1916. 



Toxoptera aurantiae Fonsc. A small black species attacking 

 the leaves and terminal shoots of lemon, Martinez, California, 

 June 12, 1916, and camellia, Camellia japonica Linn., in a lath- 

 house at Oakland. California. July 25, 1916. 



Phorodon humuli (Schrank) 

 (fig. 17). A pale yellowish green 

 aphid which during the past season 

 was first observed on the tender 

 leaves of plum on the campus, 

 April 7, 1916. At that time only 

 apterous females occurred, but on 

 April 14 a great many winged 

 migrants were present and by 

 April 25 practically all were 

 winged. The species was also 

 abundant on plum in Golden Gate 

 Park, San Francisco, California, 

 May 25. 1916. By the middle of the 

 sunnner all had become winged and 

 left the plum trees. Later in Sep- 

 tember specimens were taken on 

 hops. 



Rhopalosiphum arhitti David- 

 son. This is a fairly large green 

 and black species occurring com- 

 monh' on madrone. Arbutus men- 

 zeisii Pursh. on the campus. Other 

 trees infested are : the strawberry 

 tree Arhutus unedo Linn., campus. 

 May 18, 1916 ; the tender tips of the mountain holly or Christmas 

 berry, Photinia arhutifolia Lindl., campus, May 15, 1916. It 

 was also collected on the strawberry tree in Golden Gate Park, 

 San Francisco, California, June 5, 1916. E. P. Van Duzee of 

 the California Academy of Sciences collected it on the common 

 manzanita, Arctostaphylos manzanita Parry, at Hoberg's Resort, 

 Lake County, California, August 2, 1916. This is undoubtedly 

 Rhophalosiphum ncrvatum Gillette. 



Rhopalosiphum hon-ardii Wilson. A medium-sized, shiny 

 dark red or almost black .species associated with MacrosipJium 



Fig. 17. Phorodon humuli 

 (Sehrank) on the underside of a 

 plum leaf, Berkeley, Cal., April 

 10, 191(5. (Original. Photo by 

 Div. Sei. Illust., Univ. Calif.) 



