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Show 1884.] HYBRIDS AMONG THE SALMONIDcE. 37 the average number of bars was 9j ; the least number being eight, the most eleven, and the greatest difference between the two sides of one fish being two. Among eight pure Lochleven Trout at 9 months of age, captured November 29th, 1883, the average number of bars was 12|; the smallest number being eleven and the largest fourteen, the greatest difference between the two sides of one fish being two. These figures are remarkable as showing that at Howietoun the average number of bars in the Lochleven Trout exceeds that observed in the young Salmon. Among four young American Charr, captured November 29th, 1883, the average number of bars was eight, the smallest being seven and the largest ten, the greatest difference between the two sides of one fish being one. Among four hybrids, or rather crosses, between the American and Scotch Charr, captured July 20th, 1883, when they were five months old, the average number of bars was 9j, the smallest being eight, and the largest eleven, the greatest difference between the two sides of one fish being two. A m o n g two more hybrids of the same lot as the last, but captured on November 29th, 1883, at nine months of age, the average number of bars was llf, the smallest being eleven, and the largest thirteen, the greatest difference between the two sides of one fish being two. In this case it appears as if the number of bars has been augmented with age. So far as the evidence of the foregoing specimens bears upon the question of the number of parr-bands along the sides of young Salmonidae, they may be summed up as follows :- Largest Smallest Greatest Average. number. number, difference. 3 Salmo salar, at Howietoun 10 10 10 0 3 „ „ from the Hodder ... 9| 10 9 1 22 „ „ from Canada.. 8^- 10 7 2 3 Hybrid S. salar and S. levenensis. ll| 12 10 2 4 „ „ „ „ 11* 12 10 2 4 Hybrid S. levenensis §, S. fontinalis 3 9i H 8 2 3 Hybrid S. fontinalis 2 > & levenensis 3 9^ 11 8 2 8 Salmo levenensis 12| 14 11 2 4 Salmo fontinalis 8 10 7 1 4 Hvbrid S. fontinalis 9, 8. alpi-nls 3 9J II 8 2 2 Hybrid S. fontinalis $ , S. alpi-nus 3 Hf I*3 n 2 It appears to be a fallacy that the Salmon or migratory Salmonidae have more parr-bands than forms of non-migratory Trout-those of the Lochleven Trout at Howietoun, provided the foregoing averages are accurate, showing the greatest number of these marks; while the Canadian S. salar gives an extraordinarily small average, only equalling the American Charr. It is difficult to make out the number of bars along the sides in |