SEA-FISHERIES LABORATORY. 99 
The Food Value of Manx Herrings. 
First of all we have to consider the “‘ waste,”’ that is, the 
proportional weight of the fish that is not eaten. A certain 
number of experiments were made to find this waste value. 
The herrings (usually 3 or 5 fishes) were beheaded, and the 
viscera (except roes and milts) were removed ; the fins were cut 
‘away ; the backbone and as many as possible of the small bones 
were removed and the skin was also removed. In the salt ones 
we may eat the skin and the small bones which, when fried, are 
quite brittle and so leave nothing but head and backbone. 
Only those parts of the herring usually capable of being eaten 
were regarded as ‘‘ edible.” The results are as follows :— 
Ratio of Edible to Inedible Parts. 
Date and Origin. Edible % Inedible % 
May 11, Manx, ¢ Q, virgin ... va see 57 43 
June 21, _ ,, Ease ne we 63 37 
July 4, _,, oS a a 59 4] 
July 19, _,, --\ aes ie ne 68 32 
Sept.11, ,, ae A ige 72 28 
May 1, shop, ¢ 9, virgin ... fis eae 68 32 
LO aa 3 full ae abe <a 63 37 
May 1, Salt, 3, spent fee's Li a 62 38 
May 5, Salt, 9, full .. bs are at 73 27 
June 7, Salt, 3 Y, full i = 72 28 
‘Dec. 13, Salt, Manx, 3% full 3 oy 76 24 
Nov. 16, Kipper + aia rr 66 34 
b 
Thus the Fe aritage of caiibls pila, or ‘“‘ waste ”’ in 
fresh herrings varies between 28 and 43, while in salted herrings 
it varies between 24 and 38. These limits are not very wide, 
and it will be a safe working rule to place the proportion of 
inedible substance in good, full, Summer-caught herrings as 
about one-third. 
The variation depends upon two factors, (1) the growth of 
the reproductive organs (roes and milts) which are really edible, 
