CURRANT AND GOOSElBliRRY APHIDS IN MAINE. 5 1 



when it appears with 6 joints. Like the stem-motiier, the sec- 

 ond generation is without wings. 



As these insects reproduce rapidly the colony soon gets too 

 numerous to be sheltered by a single leaf so it scatters to infest 

 the growing shoot and underside of fresh leaves. A thriving 

 colony wih distort the shoot seriously and cause the misshapen 

 leaves to cluster in a dense protecting mass. 



In June the young aphids are found bunched aJlong the new 

 shoot so thick that there is hardly room for anything except 

 their greedy beaks to become attached. Some are a pale bright 

 tan and some are gray, the color depending apparently on the 

 length of time from a molt. The mature wingless forms and 

 pupae (individuals with black wing pads, about to become 

 winged) are dark green with short but conspicuous milk white 

 cornicles and black cauda, and the caudal part of the abdomen is 

 transversely striped with black. The colony in a mass, however, 

 has a slaty appearance on account of a fine white deposit of 

 waxy powder secreted by these plantlice and causing a "bloom" 

 on the bodies of the apterous forms. Parasited specimens are 

 often present and these are globular, tan brown objects retaining 

 the milk white color of the cornicles. 



The pupae, previously mentioned, belong to the third spring 

 generation and are abundant early in June. When these de- 

 velop wings the spring migration to the suimmer food plant 

 ta!kes place. These winged forms have head and thorax black 

 and the abdomen dark green on both the dorsal and ventral 

 surface, with transverse black bands at and caudad the corni- 

 cles. There are three large laterail black spots on the abdomen 

 cephalad the cornicle and a fourth just caudad the cornicle. 

 The Cauda is black, and the cornicles dark instead ot' milk 

 white as in the wingless forms. Antenna with sensoria in vary- 

 ing numbers on III, IV, and Y, 20 to 30 on III, 15 more 01 

 less on IV and few to several on V, sometimes a stray one or 

 two on VI besides the group at base of spur. These are shown 

 in Fig. 6 (23-10) and Fig. 7 (28-13). There is a conspicuous 



^2X322^glffiEn2I 



Fig. 6. Aphis varians. Antenna and cornicle of alate female. 



