of the Fishery Board for Scotland. 



11 



matties and mattie-fulls it ranged from 1042 to 16 68 per cent. 

 Taken as a whole, the spent fish have a lower fat-percentage than 

 the corresponding full fish ; but it is possible that in some cases 

 the fat-percentage of even spent fish may be higher than that of 

 full fish, owing to the fact that they have been feeding and 

 commenced to store fat again. 



Professor Milroy points out in comparing the West Coast and 

 East Coast fish that one is struck with the lower water and the 

 higher proteid and fat-percentages in the latter than in the former ; 

 such low fat-percentages as were obtained in some of the winter 

 West Coast herrings were never found in the East Coast autumn 

 herrings. It was found, as a rule, that the fish which possessed 

 the highest percentage of fat in their muscles had the ovaries some 

 time short of full maturity. Usually fish with ovaries of about 

 one-fourth of the weight of the ovary when fully mature contained 

 the highest percentage of fat in their muscles. There is a gradual 

 loss of fat during the later stages of maturation of the ovaries, 

 succeeded by a serious loss after the spawning of the fish. This 

 loss after spawning is evidently a very rapid one, as, although there 

 must be a short period after spawning when the spent fish contains 

 practically the same amount of fat as the full fish, it is rare that 

 one observes this in analyses, and when it is observed it is possibly 

 in some cases due to the fact that the fish is a spent fish in the 

 period of recuperation. It is after spawning that the muscles of 

 the fish lose the largest amount of their stored nutritive material, 

 and it is then that the most undoubted loss of weight occurs, over 

 and above that which can be accounted for by the complete 

 discharge of the ovaries. 



The Food of the Herring. 



Dr. Thomas Scott contributes a paper to the present Keport on 

 the food of the herring, as determined by the examination of the 

 stomachs of over five hundred specimens obtained from various 

 districts, including Loch Fyne, Stornoway, Loch Broom, and the 

 Firths of Forth and Clyde. The food observed consisted of post- 

 larval fishes (chiefly herrings, sprats, and sand-eels) to some extent, 

 but mostly of pelagic Crustacea. Among the latter the most 

 important as food for the herring appear to be certain Schizopods, 

 Amphipods, and also Copepoda, as Galanus. Dr. Scott also 

 examined into the condition known as " gutpoke," which is to be 

 observed in many of the herrings taken in Loch Fyne, especially in 

 the earlier part of the season. In this condition the stomach and 

 intestine are distended with food of a soft and oily nature, such as 

 Galanus and post-larvel clupeoids, which passes along the gut with- 

 out being properly digested and causes rapid decomposition to set 

 in. 



The Spawning, Growth, and Movement of the Mussel, 

 Horse-Mussel, and the Spout-Fish. 



On these subjects Dr. H. C. Williamson contributes a paper to 

 this Report, illustrated with a number of figures. The development 



