A SYNOPSIS OF THE APHIDIDAE 133 



156. Siphocoryne nymphaeae Linn. 



Figure 172 



Linnaeus, Syst. Nat., vol. 2, p. 734, 1735. Aphis (orig. dese.). 

 Davidson, Jour. Econ. Ent., vol. 3, p. 377, 1910. Rhopalosiplium (list). 

 Essig, Pom. Jour. Ent., vol. 4, p. 793, 1912. Ehopalosiphum (desc.). 

 Davidson, Mon. Bull. Cal. Comm. Hort., vol. 6, p. 65, 1917. Ehopalosiphum 

 (note). 



Records. Polygonum sp., Alisma sp., Potamogeton sp. ; San Francisco Bay 

 region (Davidson) : Typha latifolia; Santa Paula (Essig), San Francisco Bay 

 region (Davidson): Nymphaea sp.; San Francisco Bay region (Davidson), 

 Fresno, June, 1915: Prunus domestica; Berkeley, 1916 (Essig). 



This aphid occurs throughout the summer months on various semi- 

 aquatic plants, lily, tule, and so forth. In the fall it migrates to 

 plum, where eggs are laid. The first two or three generations in the 

 spring occur on plum, but about June there is a migration to its sum- 

 mer host plants. So far it has been found in southern California 

 only in Ventura County. 



The species listed as Aphis prunorum Dobr. (see no. 140) may be 

 this species. Essig believes it is, but the author is not certain so does 

 not list it as a synonym. 



157. Siphocoryne pastinacae Linn. 



Figures 266 to 270 



Linnaeus, Syst. Nat., p. 451, 1735. Aphis (orig. desc.). 

 Davidson, Jour. Eeon. Ent., vol. 2, p. 304, 1909. S. xylostei (Schr.) (list). 

 Davidson, Jour. Econ. Ent., vol. 2, p. 304, 1909. S. conii n.sp. (desc.). 

 Davidson, Jour. Econ. Ent., vol. 3, p. 377, 1910. S. xylostei (Schr.) and 



S. conii Dvdn. (list). 

 Davidson, Jour. Econ. Ent., vol. 4, p. 599, 1911. Hyadaphis umbellulariae 



n.sp. (desc.). 



Davidson, Pom. Jour. Ent., vol. 3, p. 399, 1911. S. conii Dvdn. (list). 

 Davidson, Jour. Econ. Ent., vol. 7, p. 133, 1914. S. xylostei (Schr.) (list). 



Records. Lonicera sp. ; Stanford University (Davidson), Claremont (Essig), 

 Berkeley, April, 1915: Umbellularia calif ornica; San Jose (Davidson): Conium 

 maculatum; Stanford University, Penryn, Placer County, and San Jose (David- 

 son). 



This aphid occurs on honeysuckle during the winter and spring, 

 and on various semiaquatic plants in the summer. It has been taken 

 in southern California, in the San Francisco Bay region, and in the 

 Sacramento Valley. 



