388 Transactions. 
Trout Foop-suPPLy. 
8 f 
the Australian frog (Hyla aurea), the toitoi (Gibiomorphus gobiordes), 
the gudgeon (Galaxias brevipinnis), and the koaro (Galaxias huttoni) 
were examined microscopically, and each found to contain enormous 
numbers of Diatoms, Algae, and Protozoa. Insect-remains were rarely 
found. 
In the years 1918 and 1919 I had the opportunity of examining the 
stomachs of a number of trout taken in the streams after the close of the 
spawning season. The stomachs of many were found to be quite empty ; 
Kendall and Goldsborough (1908, p. 47) have found the rainbow trout 
in the Connecticut lakes to subsist largely on worms and insect-larvae. 
Note is also made of the great harm done through this predatory species 
eating the eggs of salmon. 
Pearse (1918, p. 274) gives the food-example of S. irideus as follows : 
Insects and insect larvae and pupae, 43 per cent.; amphipods, 42 per cent. ; 
per cent.; amphipods, 35-5 per cent.; aquatic isopods, 0-5 per cent. ; 
terrestrial isopods, 0-8 per cent.; snails, 1-4 per cent. ; plant-seeds, 0°] 
per cent. 
Hudson (1904, p. 93) has given an excellent series of notes determining 
the species of insects and insect-larvae forming the staple food-supply of 
trout in New Zealand rivers. His results show the large extent to whic 
streams. The average trout of the Rotorua and Taupo districts is a lake 
fish associated with shoals of smaller indigenous fishes which persist in 
much larger numbers than in any New Zealand river which I have 
examined, 
Needham (1902, p. 205) has given a table of the stomach-contents of 25 
brook-trout in New York State. The results show an almost complete 
absence of food other than insects. On p. 206 he states: “І am inclined 
