

PtATE IV.— a, the female at -a'ark ^irdliup; a currant stem, natural size; 

 h, girdled portion of a stem, much enlarged, to shoiv the character o_f 

 the girdle: c, girdled portion of a stem a few days after the girdling 

 was done, much enlarged, to show the egg-scar; d, currant stem cut 

 open to sho'v the egg of the i>iscrt, much enlarged. 



