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Show 1868.] DEVELOPMENT OF THE SALMON. 249 of Charr and of Salmon-trout arrived. The Salmon-trout beo*an to be hatched on the lith of March following, and the Charr commenced hatching on the 14th of March." I am particular 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 subsequent 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 Establishment 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 maturity, but were addled. What did come forth were sufficiently different in size. During the four succeeding seasons ova have been hatched in the Gardens, hut 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 experiments, 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 in 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 period of migration of true Salmon, these, then well-marked Parr, showed no uneasy disposition 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, m y informant assures me, did not appear to have changed in the slightest. About the beo*inning of May of that year (1865), at the season of Salmon-mio*ration, those which had assumed a silvery dress grew restless, and "endeavoured to escape by leaping over the tank they were confined in ; indeed a few did spring entirely out, and died in |