CHAPTER III. 



EGGS AND ALEVINS. 



Sea-trout eggs and salmon eggs are so like each other in point of 

 size and colour that they cannot readily, if at all, be distinguished at a 

 glance. As it is the size of the individual specimen rather than the 

 species which, with these closely-related fish, determines the size of 

 the egg, the sea-trout eggs, like the sea-trout themselves, are generally 

 but not invariably the smaller. The same determining cause holding 

 good, it will be found that trout eggs in general are smaller than sea- 

 trout eggs. As a rough indication of size it may be said that four 

 salmon eggs placed in a row almost exactly occupy the space of one 

 inch, sea-trout eggs on the average rather less, and trout eggs again less, 

 although five of either of the latter will generally exceed the inch. 



I have found that twenty-six salmon eggs laid in line occupy 

 exactly the space of six inches, but I have seen an equal space occupied 

 by the same number of eggs of a well-developed sea-trout of only 

 2j lb. weight. It has been said, though I can neither confirm nor 

 disprove the statement, that the eggs of spring salmon are larger at 

 spawning time than those of autumn fish. The point does not seem to 

 be material with respect to sea-trout eggs. 



The colour of the eggs of salmon, and of most sea-trout, when they 

 are first shed, is a rich salmon pink, but on fertilisation they become 

 immediately slightly paler and more opalescent. In one respect 

 salmon eggs differ wholly from those of sea-trout and trout. The 

 colour of the former does not seem to vary at all according to locality 

 or the breed of the parents, but there is a wide range of distinctive 

 colouration in the eggs of sea-trout and trout. They may vary from a 

 pale yellow to a dark rich pink according to the locality of the breeding 



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