of the, Halm on in freak Writer. 97 



The average amount of fats, per fish of standard length, is given in 



TABLE IV. 



These results closely correspond to the results obtained in the study 

 of the changes in the total solids, but the proportionate changes are 

 even greater. 



1. In the fish coming to the estuaries the percentage of fat and the fat 

 per fish of standard length in the muscle is practically the same from 

 May on to August. The fish coming to the rivers in October and 

 November have a markedly smaller percentage of fat, and a markedly 

 smaller amount per standard fish about three-quarters of the original 

 amount. 



2. J n the ovaries, in fish coming from the sea, the percentage of fat does 

 not alter much throughout the season. In October and November it is 

 slightly higher than in the earlier months. The amount of fat in the 

 ovaries per fish of standard length undergoes no very marked changes 

 from May to August an increase of from 12 to 18 grms. But in 

 October and November there is a rise to 145 grms. This is an eight-fold 

 increase. 



3. In the upper reaches, the fish in July and August show a slight 

 increase in the percentage of fat and in the fat per fish of standard 

 length in the muscle, when compared with the May and June fish. 

 This is probably to be explained by the constant arrival of fresh fish 

 from the sea. In October and November the percentage of fat falls to 

 less than a half of the amount in the earlier months, while the fat per 

 fish of standard length shows a fall of about one-third. 



4. As compared with the fish in the estuaries, the percentage of fat, 

 and the fat per fish of standard length, in these upper-water fish is 

 very much smaller in amount. 



It should perhaps be noted that there is some indication of a 

 division of the upper-water fish, especially from May to August, into 

 two classes, one richer and the other poorer in fat. Thus in May and 

 June number 21 has a much greater amount of muscle fat than the 

 other fish of the class. 



In July and August 37 and 49 have an average of 560 grms., while 42 

 and 43 have only 391 grms. 



At first sight this would seem to indicate that some of these fish have 

 come up earlier than others, and have lost a greater quantity of fat 

 from their muscles. But a comparison of these figures with the total 

 solids and with the proteids opposes the idea that such a distinction can 

 be made. 



5. In the ovaries the percentage of fat is slightly higher in upper- 

 water fish than in the fish from the estuaries, except in October and 

 November. As already pointed out, this is probably an apparent, and 

 not a real difference. 



6. Throughout the whole season the fat per fish of standard 

 G 



