SALMON. 43 



river with the milt of a male taken from each of the three 

 ponds, the whole of which ova matured. This at once re- 

 moves any doubt which may have been entertained regarding 

 the constitutional strength of individuals reared under such 

 circumstances. 



" One of the males used in the above experiments is itself 

 the produce between a male Parr and female adult Salmon 

 taken from the river on the 4th of January, 1837, and reared 

 in pond No. 2, as already mentioned. The result of the 

 experiment practised with this specimen and the female Sal- 

 mon from the river, being of the utmost importance in estab- 

 lishing the identity of the species (on a principle recognised 

 by physiologists as a law of nature), every necessary precau- 

 tion to avoid error or confusion was observed. It was taken 

 from pond No. 2 on the 5th of January, 1839, being then 

 twenty months old, with the milt flowing from its body. A 

 female adult Salmon weighing twelve pounds was taken at 

 the same time from the river, in the act of spawning in the 

 absence of the male. A quantity of her ova was impregnated 

 in the same manner in every respect as practised in the pre- 

 ceding experiments, and, for the better security of the lot, 

 the whole was placed in a wooden trough, over which a sheet 

 of fine copper-wire gauze was fixed. The trough was then 

 placed in a stream of water previously prepared for its recep- 

 tion, and the results were precisely of a corresponding nature 

 to those already detailed, the embryo fish becoming visible 

 after fifty-five days, and being excluded from the egg at 



which one lot of ova was taken, and placed in water without impregnation, was 

 the female with which the four Parrs above alluded to were spawned. They 

 were placed in the same stream but in a separate vessel from the four lots im- 

 pregnated. The other lot was taken from the female with which the male from 

 pond No. 3 was spawned. The unimpregnated lot was placed in the same 

 stream with the former. The impregnated lot was placed in the stream of pond 

 No. 3. To avoid contact the unimpregnated lots were in each case taken first, 

 and removed to a distance. 



