350 ENTOMOLOGICAL NEWS [Nov.,'l8 



no room for reasonable doubt. Through the kindness of Mr. 

 Essig I have been permitted to examine the types of this 

 species. There are certain details in connection with these 

 types that may be passed over, and it will suffice for my pur- 

 pose to state that the material examined contains specimens 

 of three species belonging to as many different genera. 



Of these three species, one is nothing more than that previ- 

 ou.sly described by Ehrhorn as Riper sia villosa. Another is a 

 Pseudococcus that I am elsewhere describing as P. qxuercicolus. 

 The third is represented only by immature specimens, but is 

 unmistakably a species of Puto (=Ceroputo). The first is 

 the "winter form," the second is the "summer form" of P. 

 agrifoUae. The only reason that appears for regarding these 

 as forms of the same species is the fact that they were found 

 upon the same host. However, the two are morphologically 

 so very different as to render it most highly improbable that 

 they have anything to do with each other. Furthermore, the 

 evidence obtained from observations on the life history of 

 one of the species is sufficient to remove any doubt that might 

 remain. 



P. quercicohis, the "summer form" of P. agrifoUae, is 

 quite common on oaks in the vicinity of Stanford University, 

 and I have followed the species closely enough to be sure that 

 it has but one generation per year. The winter is passed in 

 the first or second larval stage, and maturity is reached in May 

 or June. In one instance I have found mature females in 

 February, but the conditions here were unique. The speci- 

 mens were found beneath the bark in old and nearly over- 

 grown borer workings in company with ants. No difference 

 appears between these individuals and those taken in the sum- 

 mer. 



Essig further states^ that "It is very probable that the 

 same dimorphic forms exist in Pseudococcus artcmisiac." The 

 reasons for this assumption are not given. I have examined 

 the types of this species, also, and find that it is identical with 

 Erium lichtcnsioides (Ckll.), a species that I know to have 



^Essig, E. O. Pomona Col. Jn. Ent. & Zoo!., vol. 2, p. 148. (1910). 



