324 



THE AMERICAN MONTHLY 



[Oct. 



are deposited beneath tlie scale, which in time hatch, 

 and tlie young larva? make their escape and migrate 

 to different parts of the plant. In the San Jose 

 scale the eggs are fairly well formed, a few at a time, in 

 the body of the mother (fig. 8). What take.^ the place of 

 the egg shell consists of a very delicate and thin mem- 

 brane — the amnion, which encloses the developing larvsB 

 and which at the time of birtli is cast off, and remains at- 



Mytilaspis pomorum : a, adult male; b, footofsams; o, ynung larva; d, antennaj of same ; e, 

 adult female taken from scale ; — a, c,e, greatly eiilargeil : b, d, still move enlarged. 



tached to or partly within the oviduct. The amnion is 

 probably pushed out 1)y the next larva in turn. Each fe- 

 male gives birth to from 9 to 10 larvae in twenty four 

 hours and as this extends over a period of six weeks it 

 leads to a very confusing intermingling of generations 

 and renders it difficult to make observations, but by iso- 



