[3] PEOPAGATION OF SCHOODIC SALMON IN 1879-'80. 735 



far exceeded that of males. The total for the season hardly bore out 

 the great anticipations which some had formed in September, but was 

 nevertheless quite respectable — 938 males, 1,084 females, total 2,022. 

 For the sake of comparison the numbers taken in other years may be 

 given, as follows : 2,628 in 1875, 1,021 in 1876, 4,151 in 1877, 2,908 in 

 1878. 



The most of the fish were measured, and the average length of the 

 females was found to be 17.2 inches, and of the males 18.9 inches. The 

 length of the females was the same as in 1878, but exceeded the average 

 for 1875, 1876, and 1877 by 1, 1.5, 1.3 inches, respectively. The length 

 of the males exceeded the average for 1875, 1876, 1877, and 1878 by 

 about 2.1, 3.2, 2.1, .7 inches, respectively. The longest male was 24 

 inches, the shortest 15 inches ; the longest female 22 inches, the short- 

 est 13 inches. 



The taking of spawn, which began November 7, proceeded without 

 noteworthy incident until November 22, when the last fish were manip- 

 ulated. In all, 978 females were deprived of their spawn, and yielded a 

 total of 1,113,456 eggs, an average of 1,136 eggs each. According to 

 our estimates the average yield for the first week was 1,205 eggs apiece. 

 These are considerably higher averages than any other season. The 

 average for 1877 was 1,066 eggs per female. 



The ratio of impregnation, deduced by careful calculation later in the 

 season, from the number of unimpregnated eggs found after the others 

 were well developed, averaged 93.3 per cent. The best result (96.5 per 

 cent.) was obtained November 19, in a lot counting 82,000 eggs ; the 

 poorest (75.6 per cent.) November 7, in a lot numbering 8,500. No nov- 

 elties were introduced in the methods of manipulation ; experience had 

 convinced me that the methods generally followed here were the best 

 for this species of fish. Many experiments were tried in 1877 and 1878 

 with a hope of discovering some mode of avoiding the serious loss by 

 reason of non-impregnation, which has always troubled us at this estab- 

 lishment, but the results had not indicated any change in the essential 

 features of our former practice. The prolongation of contact between the 

 eggs and milt was found to effect no improvement in the desired direction, 

 but to become, when excessive, a source of positive injury. One single 

 experiment tried this year illustrates this fact. November 21 a batch 

 of eggs numbering 27,156 was divided, the greater part being treated 

 in the usual way, and the smaller part, numbering 5,156, were subjected 

 to contact with the milt for 4 hours and 40 minutes. Of the former, 

 91.9 per cent, were found to be impregnated, and they turned out as 

 good as average ; the latter died, to the last egg, before development 

 was completed, being one by one picked out and thrown away. Whether 

 any improvement can be effected on the rate of impregnation attained 

 this year I am in doubt. The prevalence of ovarian disease among the 

 Schoodic salmon is, so far as can be seen, an irremediable difficulty, 

 which will probably always result in quite a percentage of eggs incapa- 



