CONFLICTING OPINIONS. 79 



see them with milt and roe^ in all the various stages, and we see 

 them perfectly empty; all which circumstances clearly prove 

 that they are a distinct species." 



Clearly, indeed ; if it appear that these circumstances can be 

 authenticated ; but this I, for the present, doubt — First, because 

 if there had been visible facts, the theory never could have been 

 started of their being unproductive mules. Second, because 

 Sir WilHam Jardine, after examination of the Parr of the Tweed, 

 speaks of it as still uncertain whether it may not be the young 

 of the Common Trout {Salmo Fario) ; and for this reason, that 

 though he has found males full of milt, he never has seen 

 females with the roe in an advanced state ; and, furthermore, 

 distinctly avers, that " they have not been discovered spawning 

 in any of the shallow streams or lesser rivulets, like the Trout." 



Sir William, however, still leans to the opinion that there is 

 a distinct species, in which the transverse markings are perma- 

 nent, which reproduces its own kind, and never grows to a 

 greater size than eight or nine inches ; and this he would retain 

 under the title given to it by Ray, of Salmo Salmulus. 



Mr. Yarrel is of the same opinion ; and has certainly shown 

 decidedly that it is not a hybrid, or a species of which there are 

 no females, as had been surmised ; since of three hundred and 

 ninety-five Parrs, or Samlets, examined by Dr. Heysham, one 

 hundred and ninety-nine were males, and one hundred and 

 ninety-six females. 



The great point, however, is this, which is now, I think, per- 

 fectly clear, and which at once dispels all the mystery of the 

 question, namely, that the young of all the SalmonidcB — not 

 several only, as Sir William Jardine and Mr. Yarrel state, but 



