34 8AI.MON. 



Mv. SIkiw jit'tcrwarcls impregnated the ova of the 

 Salmon with the milt of the common River Trout, 

 according to my suggestion ; and in a letter with which 

 he favoured me, dated 26th of April, 1841, he says: — 

 " I am happy to inform you that my experiments with 

 the ova of the common Trout and Salmon have been 

 quite successful, and the young hybrids are now hatched, 

 and in good health." Mr. Shaw will, of course, publish 

 the details of his late expei'iments, and thus add to the 

 obligations which those who are interested in this sub- 

 ject already owe him. 



I will only add, that his papers arc written Avith such 

 candour, and all his experiments conducted with such 

 care and al)ility, and so often repeated with similar 

 results, without any effort or intention to make tliem 

 bend to a favourite theory, that every one, I think, 

 who reads his pages, must consider that the Parr and 

 the Salmon are of the same species, and that the 

 question is so far set at rest for ever. 



To sum up, — it appears that the young fry had burst 

 the egg 101 days after impregnation, the temperature 

 of the water being at that time 43°, and the temperature 

 of the atmosphere 45° : a former brood, which died and 

 Avere excluded in a colder temperature, did not come 

 into life till 1 14 days after impregnation. 



It further appears from a part of Mr. Shaw's publi- 

 cation, Avhich I have not hitherto quoted, but which I 

 have now before me, that the fry, at two months old, 

 are only one inch and a quarter long ; at four months, 

 two inches and a half; and at six months, three inches 

 and a quarter : that makes nine months and eight days 



