256 Some Observations on the Egg of Psylla mali 



but on the inner membrane is shown by the fact that a newly hatched 

 larva or one in which hatching has been induced artificially is perfectly 

 free from them (Fig. 7). 



mouth parts 



dark area 



-j^--N-- anus 



Fig. 7. Larva removed from egg membranes. 



Position of larva in egg membranes. In Fig. 8, the original of which 

 was prepared by carefully treating an egg with the bleaching powder 

 mixture, the larva is shown in situ. The outer membrane is nearly 

 dissolved away and the process of the middle membrane can be seen 

 partially withdrawn from its normal position. The larva lies with 

 its anterior end at the pointed end of the egg with its ventral surface 

 towards the twig. Its posterior end is towards the hollow process 

 and its closely packed legs are situated immediately over it. 



eye 



Fig. 8. Relation of larva to membranes. 



At first it was thought that possibly the mouth parts went down 

 the hollow process and served as a physiological connection between 

 the apple tree and the egg. When examining specimens of the entire 



egg some straight lines could !><• seen in the hollow process of the outer 



