50 MAINE AGRICULTURAL EXPERIMENT STATION. I914. 



as I should have hked. With so many species mixed on the 

 same hostplants, however, Maine does not seem a very satis- 

 factory field for follov/ing up the life cycles of the Ribes aphids 

 and the present paper is prepared more especially to call atten- 

 tion to the perplexities of the situation in hopes that other 

 workers may have some of the missing links to contribute. 



Aphis varians, n. sp. 



White cornicled currant aphid. 



Figs. 5, 6, 7, 34, 39. 



By far the worst of the species under consideration is a plant 

 louse which I fail to find recognizably described. It m.ay be 

 grossularicB Kalt, but that name has been applied to several dif- 

 ferent species and it seems best to hold this distinct at least tor 

 the present. It is abundant upon cultivated currant, flowering 

 currant, and wild gooseberries at Orono during the months of 

 May and June, and complaints from \\''est Paris, Maine, ac- 

 companying specimens state that it was present there in such 

 numbers in the springs of 1910, 191 1 and 1912 as to stunt the 

 growth of the bushes and cause the leaves to turn brownish. 



In Maine the stem-mother, that is the form which hatches 

 from the over-wintering eggs, becomes full grown early in May 

 if the weather conditions are right. During her growth she 

 stations heself on the underside of a currant leaf which becomes 

 puckered from the injuries caused by her feeding punctures. 

 There in the protecting irregularities of the leaf she has de- 

 formed, she gives birth to a numerous progeny. When mature 

 she is dark purplish green with a black "tail" or cauda, con- 

 spicuous milk white cornicles, and a 5-jointed antenna. (Fig. 

 5.) Her immediate progeny, the second spring generation, are 



Vig. 5. Aphis varians. Antenna of stem female. 



dark green to dark brown. When they are first born their an- 

 tenna is 4- jointed but the number of joints is increased to 5 at 

 a subsequent molt which number it retains until the last molt 



