A SYNOPSIS OF THE APHIDIDAE 137 



0.178 mm.) ; IV, 0.068 to 0.119 mm. (av. 0.0855 mm.) ; V, 0.068 to 

 0.102 mm. (av. 0.0833 mm.) ; VI, 0.068 to 0.119 mm. (av. 0.085 mm.) ; 

 spur, 0.085 to 0.136 mm. (av. 0.117 mm.) ; cornicles, 0.306 to 0.442 

 mm. (av. 0.3655 mm.) ; cauda, 0.204 to 0.272 mm. (av. 0.2338 mm.) ; 

 hind tarsi, 0.102 mm. (Note : no color notes were taken of the apterae 

 at the time of collection and as all the specimens were killed in alcohol, 

 dehydrated in xylene and mounted in Canadian balsam, it is impossible 

 to give any color notes.) 



35. Genus Coloradoa Wilson 



Wilson, Ann. Ent. Soc. Am., vol. 3, p. 323, 1910. Type Aphis rufomaculata 

 Wilson. 



This genus was described by Wilson in 1910 to contain the species 

 Aphis rufomaculata Wilson. After examining specimens of this 

 species recently, the author is of the opinion that Coloradoa and 

 Myzaphis are synonymous, for there does not seem to be enough differ- 

 ence between this species and the two species of Myzaphis to warrant 

 a separation of genera. However, the author does not feel certain 

 concerning the point, so lists both these genera. Should they later 

 prove to be synonymous, Myzaphis would have to be dropped and 

 replaced by Coloradoa. There is but one species belonging to this 

 genus. 



160. Coloradoa rufomaculata Wilson 



Wilson, Ent. News, vol. 14, p. 261, 1908. Aphis (orig. desc.). 

 Eecord. Chrysanthemum, cultivated; Sacramento, April, 1917 (Davidson). 



The author has recently received specimens of this species from 

 Davidson taken on chrysanthemum in Sacramento. 



36. Genus Cerosipha Del Guercio 



Del Guercio, Nouve relazione agraria di Firenze, vol. 2, p. 116, 1909. Type 

 C. passeriniana n.sp. 



161. Cerosipha cupressi Swain 



Swain, Trans. Am. Ent. Soc., vol. 44, p. 19, 1918 (orig. desc.). 

 Records. Cupressus guadelupensis ; San Diego, 1916; Riverside, 1917; C. 

 macrocarpa, San Diego, 1916. 



This species, recently described by the author, has been taken by 

 him several times in San Diego and Riverside on blue cypress and 

 Monterey cypress. It is an extremely interesting little aphid, differ- 

 ing considerably from any other species known to the author, both 

 in habits and appearance. Its five-jointed antennae, long cauda, 

 atrophied cornicles, and convexity of abdomen are quite distinctive. 



