1884.] HYBRIDS AMONG THE SALMONID.E. 37 



the average number of bars was 9 3 ; 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 29 th, 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 9|, the smallest being eight, and 

 the largest eleven, the greatest difference between the two sides of 

 one fish being two. 



Among two more hybrids of the same lot as the last, but captured 

 on November 29th, 1883, at nine months of age, the average num- 

 ber of bars was llf, the smallest being eleven, and the largest thir- 

 teen, 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 Sal- 

 monidse, they may be summed up as follows : — 



Largest Smallest Greatest 



Average. number. number, difference. 



3 Salmo salar, at Howietoun 10 10 10 



3 „ „ from the Hodder ... 9£ 10 9 1 



22 „ „ from Canada 84, 10 7 2 



3 Hybrid S. salar and S. levenensis. l\\ 12 10 2 



4 „ „ „ „ 11* 12 10 2 

 4 Hybrid 8. levenensis 9, 8. fonti- 

 nalis 3 94 11 8 2 



3 Hybrid S. fontinalis 9. , 8. leve- 

 nensis J 9g 11 8 2 



8 Salmo levenensis 12| 14 11 2 



4 Salmo fontinalis 8 10 7 1 



4 Hybrid 8. fontinalis 9 , 8. alpi- 



mis J 9* 11 8 2 



2 Hybrid S. fontinalis 9 , S. alpi- 



nls 6 •• U i Vd U 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, oniy 

 equalling the American Charr. 



It is difficult to make out the number of bars along the sides in 



