CURRANT AND GOOSEBERRY APHIDS IN MAINE. 



53 



The 5- jointed antenna of the stem motlier (Fig. 8) (23-13) 

 is not strikingly different from that of varians in its proportions. 



Fig. 9. Aphis sanborni. Antenna and cornicle of nymph. 



The apterous second generation has during the nymphal 

 stages a 5-jointed antenna, Fig. 9, which becomes 6-jointed at 

 the last molt. Fig. 10. This is without sensoria except the 

 usual ones on V and VL 



Fig. 10. Aphis sanborni. Antenna oif apterous female. 



The winged female of sanborni has antenna with 6 or 8 large 

 circular sensoria in a row extending the full length of III, 6, 

 more or less, similarly arranged on IV and none on V" or VI 

 except the terminal ones which are constant for those joints in 

 all aphids. (Fig. 11.) The wing is shown in Fig. 35 and the 

 imbricated cornicle in Figf. 11. 



Fig. II. Aphis sanborni. Antenna and cornicle of alate female. 



I do not know the full cycle of sanborni. A collection taken 

 May 28, 19 1 3, from the leaves and stem shown in Fig. 29 

 comprised stem females, apterous females of the second genera- 

 tion, and pup« with wing pads well developed. It would seem 

 evident from this that the gooseberry is the winter host but 

 concerning the rest of the cycle I know nothing. 



Rhopalosiphum lactuccef Kaltenbach. 

 Figs. 19, 20, 21, 22, 40. 

 A plant louse common in Maine upon currant in spring is 

 probably the same as a similar one on sow thistle (Sonchns 



