58 BRITISH" APHIDES. 



from the numerous eggs which fill the body-cavity. 

 Head- and tail-ends slightly browner. Eyes black and 

 very small. Antennas short and very fine, three- 

 jointed, the last being much the longest. Legs very 

 small, scarcely protruding beyond the body. Rostrum 

 about one-fourth the length of the body. 



This insect is the immediate produce of the true 

 ovum, which was laid in the autumn by the sexed 

 female. Her history, after exclusion from the egg, is 

 probably somewhat different according to the climate, 

 and, perhaps, the character of the vine on which it 

 occurs. 



The aerial forms are rare in the colder countries, 

 but they increase in frequency as we go southwards or 

 cross into America. Where the aerial forms occur, the 

 foundress punctures the leaves in such a manner that 

 the swelling masses close over and finally entomb 

 her. The leaves become studded over the surface (and 

 particularly near the edges) with gall-like masses, 

 many of which are pedunculate. Each foundress 

 appears to form a single gall, within which she lays 

 hundreds, or even thousands, of yellow egg-like bodies. 

 This oviposition continues through the summer, after 

 which operation she dies. 



These galls are round, fleshy, and corrugated. They 

 often number a hundred or more upon a single leaf. 

 A vine which is much infected soon becomes sickly. 

 The leaves show distortion, turn yellow or brown, 

 and during their decay yield a faint and unpleasant 

 odour. The stocks become stunted, and if the 

 roots be uncovered they will be found (especially 

 as regards the fibrils) swelled into small blebs and 

 tubercles. These are the result of the attacks of the 

 young Phylloxeras, which, after their development on 

 the leaf and escape from the gall, have descended into 

 the ground and commenced their subterranean exist- 

 ence. These creatures are so numerous that the roots 

 wlicn turned up often appear dusted with yellow 

 grains. In this condition they produce the greatest 



