1868.] DEVELOPMENT OF THK SALMON. 249 



of Chan- and of Salmon-trout arrived. The Salmon-trout began to 

 be hatched on the 11th of March following, and the Charr com- 

 menced hatching on the 14th of March." 



I am jsarticular in noting these details, so that all possibility of 

 error or mistake may be fully made known. 



On Mr. Bartlett's and Tennent's authority I may state that 

 each of these batches of ova, on their arrival and during the sub 

 sequent processes of hatching and of rearing, were scrupulously kept 

 separate from each other. The different dates of arrival and of 

 evolution from the egg further prevented confusion. 



Concerning the Rhine Salmon and the Great-Lake Trout, Mr. 

 Frank Buckland himself received these from the Fish-rearing Esta- 

 blishment at Huningue, near Basle. If it cannot be authenticated, 

 it is presumed the ova were such as represented. The precise Swiss 

 lake which the Trout were inhabitants of I have not learned. 



In 1864, ova of Salmon, Great-Lake Trout, Common Trout, and 

 hybrids between Salmon and Trout were duly added to the Society's 

 collection. Some of these, chiefly the hybrids, never reached ma- 

 turity, but were addled. What did come forth were sufficiently 

 different in size. 



During the four succeeding seasons ova have been hatched in the 

 Gardens, but in limited quantities. 



Great care, however, has always been taken that the ova both of 

 the different species, seasons, &c. should be kept separate. In fact, 

 as the whole has been considered in the light of scientific experi- 

 ments, and with the watchful eye of Mr. Bartlett over them, besides 

 numerous observers well versed in ichthyology constantly visiting the 

 fish-house and overlooking the experiments, there is little room left 

 for doubt as regards the data occurring during the earlier periods of 

 their development in our establishment. 



Some of the aforesaid ova of the Rhine Salmon, successfully 

 hatched in the Gardens in February 1863, have lived m fresh water 

 alone up to the present date. Regarding these (two in number) I 

 shall say more presently. 



From a dozen to twenty in number, according to Mr. Tennent, 

 lived between two and three years in the above condition (viz. in a 

 small tank with a running stream of fresh water), and in apparent 

 health. 



After they were a year old, at the usual ])eriod of migration of 

 true Salmon, these, then well-marked Parr, showed no uneasy dis- 

 j)Osition or tendency to escape from their tank. 



In the second year some of them had slightly altered in colour, 

 the Parr markings becoming somewhat indistinct ; and a tendency to 

 a silvery- scaled appearance ensued. But this change did not occur 

 to all. About a third of the total number, my informant assures 

 me, did not appear to have changed in the slightest. 



About the beginning of May of that year (1865), at the season 

 of Salmon-migration, those which had assumed a silvery dress grew 

 restless, and endeavoured to escape by leaping over the tank thev 

 were confined in'; indeed a few did spring entirely out, and died in 



