144 Dr. W. E. CoUinge on Me [Ibis, 



injuiioTis insects 15*5 percent., neutral insects 4"5 per cent., 

 Crustacea 6*5 per cent., molluscs 5*5 per cent., tadpoles 

 4"0 per cent., worms 1"5 per cent., and miscellaneous animal 

 matter 3'0 per cent. 



The lightest nest-content weighed 12"5 grains and the 

 heaviest 320 grains, the average being 142 grains. In all 

 probability the heavier ones represent the contents accumu- 

 lated over more than one season, but on this point I have no 

 definite information. 



Of the 59*5 per cent, of fish, minnows constituted 39*5 per 

 cent., stickleback 31"0 per cent., gudgeon 14"5 per cent., 

 trout 12"5 per cent., and 2'5 per ceist. of unidentifiable fish- 

 remains. 



2. Pellets. — The average weight of the pellets was 15 grains. 

 The analysis of the fifty-three specimens shows that they 

 consist wholly of animal matter of which fish constitutes 

 590 per cent., injurious insects 15'0 per cent., Crustacea 

 6"0 per cent., tadpoles 5*5 per cent., moUuscs 5"0 per cent., 

 neutral insects 5*0 per cent., worms 1*5 per cent., and 

 miscellaneous animal matter 3'0 per cent. 



V. Examination of Stomach Contents. 



Practically all the stomachs examined were full. The 

 average weight of the contents was 32'5 grains. Only twenty- 

 seven stomachs have been examined. It was evident at a very- 

 early stage of this inquiry that the pellets and nest-contents 

 afforded a very valuable source of information, and one 

 Avhich was in close agreement with the results obtained from 

 the post-mortem examinations. It was, therefore, not thought 

 desiral)le to destroy a large number of birds for the purpose 

 of examining the stomach-contents. Many of those examined 

 have been kindly sent to me by taxidermists, to whom the 

 birds had been sent or brought to be set up. 



1. Nature of the Food. — An examination of the stomach- 

 contents shows that the whole of the food consists of 

 animal matter. Specimens have been examined in all the 

 months of the year excepting May, June, and December. 



