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Part III. — Twenty -fourth Annual Report 



(3) The fat percentage of the ovaries is highest, evidently, in the case 

 of Loch Fyne herrings between the months of July and September. It 

 is low at the time when the amount in the muscles is high. The absolute 

 amount of fat in the ovaries per average fish is, of course, highest in the 

 case of the large November and December fish. With the onset of 

 spawning the absolute amount of fat begins to fall. 



The total amounts of P 2 0 6 in the muscles and ovaries are highest 

 during the months of November and December. 



(4) The ratio of muscle proteid to ovarian proteid practically is the 

 same as that between total weight of fish and total weight of ovaries (see 

 tables, pp. 97, 98). 



(5) The ratios between the muscle proteid and muscle fat, and ovarian 

 proteid and ovarian fat are shown clearly in the table on p. 97. 

 The most important ratios are those between the muscle proteid and 

 muscle fat. Owing to the rise in the fat percentage during September, 

 October, and November, it gradually approaches that of the proteid, and 

 in the case of the October A series actually rises above the latter. 



(6) The ratio between the muscle fat and ovarian fat is given in the 

 table on p. 98. 



(7) The composite table on p. 100, giving analyses of male muscle 

 and testes is not sufficiently complete to enable one to draw definite 

 conclusions from it, except in so far that the male muscle evidently under- 

 goes the same changes as the female. 



In the light of the above facts, it is interesting to compare the principal 

 feeding times for these herring with the variations in their composition. 

 Brook and Calderwood (Report on the Food of the Herring, Fourth Annual 

 Report of the Fishery Board for Scotland, Edin., 1886, Appendix F. No. 

 VI., pp. 102-128) state that on the West Coast of Scotland the principal 

 spawning time is from February to April (e.g., on the Ballantrae coast), 

 while the principal feeding time is from April to September. The 

 principal food is copepods, which are taken practically exclusively from 

 April to June. Towards the end of the feeding time they are practically 

 replaced by schizopods. 



The spawning takes place, just as in the case of the East Coast fish, 

 six to eight months after the richest feeding. 



Heincke (" Naturgeschichte des Herrings," p. 48) has shown that the 

 herring after spawning seeks a place where it can get ample food 

 to recuperate. For example, the herrings of Schley, after leaving the 

 spawning beds in June, take three or four months to feed up in Kiel 

 Bay. In September and October they are fattest, and then begins anew 

 the development of the reproductive organs, which up to this time was 

 checked. This takes up the whole autumn and winter, the fish still 

 taking food, but it is not used for the building up of fat, but for the 

 development of the genitalia. With the increase in the development of 

 the genitals, the desire for food diminishes until spawning time arrives, 

 when no food is taken at all. There are thus three periods in the yearly 

 life of the Schley herring : — 



1st. The restitution or the feeding period. This continues for 3-4 

 months after spawning and is the principal feeding time. The 

 spent thin fish during this period recovers and lays on a large 

 amount of fat. 



2nd. The ripening period. This continues for 6-7 months. The 

 herring still continues to eat but gradually with less desire, while 

 the sexual organs increase at the expense of the fat. 



3rd. The spawning period. This continues for 2 months, and 

 during this time feeding stops. 



