STRUCTURE OF 



305 



nature of gills; for the larva lives under water in streams 

 and ditches, enclosed for the most part in a tube of earth. 

 It is of a fine crimson colour, the origin of its popular 

 name; but it becomes more dark and opaquein the pupa 

 state. 



The appendages which are thrown off by the larva 



a, Chironomus ptuvwsus. 5, larva of the same, called the Blood worm, 

 d, pupae of ihe same, magnified to show their plumed spiracles. 



VOL. vi. 26* 



