OCR Text |
Show 32 DR. J. MURIE ON IRREGULARITY [Jan. 13, highest consequence as regards the determination of species, supposed transition of allied forms, and questionable hybridity. With these remarks I proceed to reproduce m y previously suppressed discussion of facts and published data. AFFIRMATION. I. The historical evidence.-What points to the truth of this (i. e. that the fish described are Salmon) has already been given (see P.Z. S. 1868, p. 247); but it undoubtedly contains a weak point; otherwise the whole matter were settled. While the ova received in the Gardens on the 8th January, 1863, may have, as related, veritably undergone all the subsequent changes ascribed, this does not prove their being in the first instance ova of Salmo salar. Messrs. Buck-land and Bartlett assume them to have been so, and add validity by stating that the size and appearance of the ova convinced them of their genuineness ; for the ova of the Great-Lake Trout differ sufficiently to be recognized by the naked eye. As a sequel to the heretofore described specimens, it is most important to note that one of the fish produced from the ova of the Rhine Salmon, hatched in the Gardens in February, 1863, died on the 1st December, 1867. It was sent to Mr. Frank Buckland, who found on examination that it was a pregnant female. He states that 117 ova, nearly ripe, were present in the abdominal cavity, lying perfectly loose therein. This female weighed 4 oz., and measured 8| inches in length. Mr. Buckland believes " that, had this fish lived another fortnight or three weeks, these ova would have been quite fit to be deposited in a nest, after the fashion of an ordinary full-grown salmon that had made its two or three journeys from the fresh water to the sea" *. II. External resemblances to Salmon.-It can hardly be denied that, so far as external appearance is concerned, the fishes bear the stamp of young Salmon in the Parr condition. This applies more especially to that figured as No. 1 (Pl. XXIII. P. Z. S. 1868) ; the other, No. 2 (/. c ) , is more brindled and spotted than is commonly the case in the Parr; but this in part may be due to the nature of its habitation. The form of the bodies, the relative dimensions of snout to head, head to body, shortness of maxillary, colour of adipose fins, dentition, shape of caudal fins, and contour of prseopercu-lum all agree with Salmo salar, and not with other species of Salmo. III. Published statements and experiments.-Reference to a few of the better substantiated cases of Salmon reared and continuously kept in fresh water may be interesting at this juncture. 1. Yarrell (Brit. Fishes, vol. i. p. 172, 3rd edit. 1859) mentions that a Scottish landed proprietor in 1831 put some Salmon-fry into a freshwater pond. These were taken out in 1833, to all appearance * See an account of this interesting specimen in ' Land and Water' for Dec. 7 1867, vol. iv. p. 320. Preserved in spirits as a preparation, this same fish was shown at the Meeting the evening the former paper was read. It now forms one of the series in the Museum of Fish-culture at the Horticultural Gardens. |