26 SALMONID^E. 



a fin or fringe, resembling that of the tail of the tadpole, 

 which runs from the dorsal and anal fins to the termination of 

 the tail, and is slightly indented. This little fish does not 

 leave the gravel immediately after its exclusion from the egg, 

 but remains for several weeks beneath it with the bag at- 

 tached, and containing a supply of nourishment, on the same 

 principle, no doubt, as the umbilical vessel is known to 

 nourish other embryo animals. By the end of fifty days, or 

 the 30th of May, the bag contracted and disappeared. The 

 fin or tadpole-like fringe also disappeared by dividing itself 

 into the dorsal, adipose, and anal fins, all of which then 

 became perfectly developed. The little transverse bars, 

 which for a period of two years (as I have already shown) 

 characterize it as the Parr, also made their appearance. 

 Thus, from the 10th of January till the end of May, a 

 period of upwards of one hundred and forty days was required 

 to perfect this little fish, which even then measured little 

 more than one inch in length, and corresponded in all re- 

 spects with those on which I had formerly experimented, as 

 well as with such as existed at that same time in great num- 

 bers in the natural streams. 



" Although I was myself satisfied by the preceding facts 

 that Parr and Salmon fry were thus identical in kind, and 

 differed only in respect to age, I was informed that my in- 

 ferences were objected to, in as far as there was not suffi- 

 cient evidence that the spawn experimented on was actually 

 that of Salmon, seeing that the same streams were accessible 

 to other species of the genus. I therefore felt it incumbent 

 on me to supply this desired link in the chain of evidence, 

 and I accordingly repeated my experiments on ova which I 

 saw excluded, which, in fact, I forced the Salmon to exclude, 

 in the manner after mentioned, preserving at the same time 

 the skins of the parent fish, for the satisfaction of the curious 

 or sceptical. 



