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of animal food, while it again is pursued by the tunny, the 

 sharks, dog-fishes, and other forms stronger than itself. 



The herring, so valuable to the fishermen of these islands, 

 is another gregarious form, appearing and disappearing 

 from some places in a way often inexplicable to the fisher- 

 men. If, however, an investigation were made, it is pro- 

 bable that their seemingly eccentric movements may be 

 caused by the appearance or diminution of some peculiarly 

 acceptable description of food on which they subsist : this 

 is generally held to consist of minute shrimp-like crus- 

 tacea, often of forms belonging to the same division as the 

 common Cyclops of our fresh waters. But it is also evident 

 that it feeds upon very varied forms of animal life, and 

 probably is not particular what it is, providing it can obtain 

 sufficient. In February, 1882, I found that some sent me 

 by Mr. Dunn, from Mevagissey, had been feeding upon 

 annelids : from the same locality in the middle of May 

 their stomachs were crammed with sand-launces (Ammo- 

 dytes\ some of which were up to 2\ inches in length, and 

 as many as nineteen were inside one herring, while the 

 sand-launces in their turn were full of the remains of 

 Crustacea. A month later from the same place and cap- 

 tured about eight miles off shore, the food had again 

 changed and consisted almost entirely of the young of a 

 very rare gobioid fish (Crystallogobius Nilssonii), the largest 

 of which was i^ inches long, there were also a few young 

 herrings and sand-launces. At the end of May, 1883, 

 herrings were again found to be gorged with the young of 

 the C. Nilssonii) a remarkable fact, as only one adult speci- 

 men of this Scandinavian species has been recorded from 

 the shores of the British Isles, and that was obtained by 

 Mr. Edward, of Banff. From whence then do the herrings 

 follow these little gobies ? 



Knox obtained from the stomachs of some herrings from 



