630 E. N. PAVLOVSKY 



ecdyses changes somo structural characters, especially in the 

 antennae, the under-lip, and partly the pleural appendages. 



In the literature the excellent drawing of the mature larva 

 given by Schiodte is generally adopted ; hui I have not been 



Text-fig. 1. 



Hydrophilus caraboides. A larva, first stage. 



able to find any figure of a young larva, therefore I here adduce 

 its figure, drawn unfortunately from a specimen preserved in 

 spirit, on account of which the abdomen seems shorter than 

 it is in reality (Text-fig. 1). It is true that it easily extends, 

 a fact which causes some variation in its length even under 

 normal conditions. 



These facts found by me caused me to investigate the larvae 



