ADDITIONAL NOTES. 297 



seasons are in favour of it. Thus, in the autumn and beginning 

 of winter, I have found in the parr the milt voluminous, and 

 ready, or nearly ready, to be shed ;* whilst in the spring, in the 

 sinolts, I have hardly found a vestige of it, as if it had been shed. 

 On the contrary, in the female, at the former period, I have 

 found the ovaries very small, the ovaries rarely sufficiently 

 advanced to appear granular, but gradually, though very slowly, 

 increasing in volume towards spring, so slowly, indeed, that 

 when prepared to migrate, in the majority of females they are 

 hardly granular. That in the grilse the ova are matured, that 

 it, after its first return from the sea, is a breeding fish, appears 

 to be proved beyond doubt. 



All the Salmonidse, it would appear, breed early in life, size 

 of body being little concerned with the faculty of breeding. Nor 

 is this surprising, when we reflect that the ova and the spermato- 

 zoa are of the same magnitude, whether the product of fish in 

 early life or in advanced, the great difference being as to number. 

 This precocity is a happy circumstance, and designed, no doubt, 

 to secure the continuance of the species, in so many ways endan- 

 gered. These remarks may help to make accord Mr. Shaw's and 

 Mr. Young's observations : one, that the male parr mates or 

 follows the old female salmon, when breeding, to secure the 

 impregnation of her ova ; the other, that the female prefers a 

 male of about her own age, and takes no note of the parrs, even 

 selecting a trout for her mate, in case of need, not being able to 

 find a salmon ; and that the ova of the salmon can be fertilised 

 by the sperm of the trout, we are assured by Mr. Shaw, after 

 trial of its influence. The subject is a curious and important 

 one. Analogies may be found amongst other animals, and even 

 amongst some considered of higher organisation. The goat and 

 the sheep may be mentioned as instances. Like the salmon and 

 trout, they breed together ; like them, the male is more preco- 



* Of three parrs taken in St. John's Beck, in the first week of September, 

 1850, the milt of one the entire fish weighing 525 grs. and measuring 

 5.7 inches in length, was 114 grs.; of another, weighing 327 grs. and mea- 

 suring 4.6 inches, was 52 grs.; of a third, weighing 445 grs. and measuring 

 5.5 inches, was 84 grs. In these instances, though the milt was propor- 

 tionally so voluminous, it was not even in the first quite mature, not yielding 

 on pressure the milky fluid characteristic of its maturity. Five weeks later, 

 I have taken the parr in the same stream, with its testes arrived at this 

 stage of maturity ; others, taken at the same time, were found in various 

 degrees less so. 



