38 MISCELLANEOUS STUDIES 



36. Symydobius agrifoliae Essig 



Essig, Univ. Calif. Publ. Entom., vol. 1, pp. 311-317, 1917 (orig. desc.). 

 Eecords. Quercus agrifolia; Santa Paula (Essig). 



This interesting aphid was taken in Ventura County on live oak 

 during 1911. It differs from other members of this genus in the 

 extremely short spur of the sixth antennal segment. The coloration 

 is very similar to that of the next species, but the length of VI spur 

 and the fact that the anal plate is not bilobed serves to distinguish it. 



37. Symydobius chrysolepis Swain 



Figures 269 to 274 



Swain, Trans. Am. Ent. Soc., vol. 44, p. 6, 1918 (orig. desc.). 

 Eecords. Quercus chrysolepis; Alpine, San Diego County (Swain). 



This is a medium sized, brownish colored aphid found in 1916 

 infesting the terminal twigs and leaf petioles of maul oak in San 

 Diego County. Its pale white cornicles are very conspicuous, and 

 serve as a distinguishing character. The anal plate is bilobed, a char- 

 acter not found in other members of the genus, and one which may 

 be sufficient for the separation of the species (and 8. albisiphus Davis, 

 in which the anal plate is also bilobed) from Symydobius into a new 

 genus. However, the author believes it best to retain them in this 

 genus at present. The apterous females were found to be heavily 

 parasitized by the chalcid fly, Closterocerus utahensis Crawford var. 

 calif ornicus Girault. 



38. Symydobius macrostachyae Essig 



Figure 73 



Essig, Pom. Jour. Ent., vol. 4, p. 727, 1912 (orig desc.). 

 Eecords. Salix macrostachya ; Santa Paula (Essig), Fresno, June, 1915. 



Twice has this species been taken, once by Essig near Santa Paula 

 and once by the author along the San Joaquin River near Fresno. 

 It is found in fairly large colonies on the younger stems of willow. 

 These colonies consist for the most part of apterae, only a very few 

 alates being present. 



