200 STUDIES IN INSECT LIFE, ETC. 



like-looking objects Probably each pupa takes 

 some three-quarters of a year to develop into 

 the adult fly, and the latter disappears from 

 October until June. There is thus a certain 

 tragedy in the life of these insects. No parent 

 ever sees its offspring, no offspring ever knows 

 parental care. We have never found one of these 

 flies in the crop of the grouse, nor have we suc- 

 ceeded in finding cysts in the bodies of flies which 

 were broken up, or teased up, or cut into sections 

 and examined under the microscope. 



Finally, there is another fly whose larva lives 

 in grouse droppings. All these creatures have 

 been carefully searched for the larva of the 

 grouse tape-worms, but so far with no definite 

 success. 



Of the fifteen endoparasites but two or three 

 demand attention ; the others are compara- 

 tively rare or innocuous, and some, such as the 

 gape or forked worm so fatal to pheasants, 

 are not normally parasites of the grouse. Occa- 

 sionally by some accident they get into the 

 wrong Paradise. 



These endoparasites, which live inside the 

 body of the grouse, are responsible to some 

 extent for the illnesses from which grouse suffer. 



