THE SALMON FAMILY 59 



In the young salmon the head is shorter than in that 

 of the brown trout ; there are nine or ten finger marks 

 across the body, and the adipose fin is slaty blue in 

 colour. 



The sea-trout has the same number of markings, but 

 the adipose fin is orange tipped. 



In the brown trout there are usually only six or seven 

 finger marks, and the adipose fin is red in colour. 



Salmon parr and trout fry differ slightly in their 

 methods of feeding, for salmon parr feed mainly on 

 food under the stones, whereas trout fry feed on food 

 carried along in the water. 



Returning to the salmon parr, we left him two or 

 three inches long at the end of his first summer. During 

 the winter the little fish lives in a comatose state under 

 a stone, and takes no food. In the early spring he again 

 emerges as a dark, lanky little fish, but as the water 

 becomes warm, parr again assume their active habits 

 and make their way up every little stream, and swarm 

 in the shallow running waters of salmon rivers. During 

 their second summer parr double their weight; but 

 when winter arrives they again retire into shelter. 



In the following spring, that is, when the parr is just 

 over two years old, the little fish gather together in 

 shoals, and a complete alteration takes place in then* 

 appearance, for the back becomes of a dark bluish shade, 

 and the sides a silvery hue. The parr is now described 

 as having put on his " sea jacket," and is known as a 

 smolt. 



