22 THE SILVERY HOSTS OF THE NORTH SEA. 



are hunted by the cod-fish and other deep swimmers ; 

 while, if they rise to the top, surface swimmers and 

 sea birds follow them as long as they remain in sight. 

 If the herring were not possessed of enormous re- 

 productive powers, they would long ago have become 

 as extinct as the dodo. 



Frank Buckland, in his Report, gives the following 

 table as the result of his calculation of the number 

 of eggs carried by the female : 



Bloch, in his history of the herring, computes the 

 number at 68,000 ; other ichthyologists give from 

 21,000 to 36,000. M. de la Blanchere gives 70,000; 

 the great difference between the numbers stated 

 above may, perhaps, be reconciled if we suppose the 

 examples to have been taken from fish of different 

 ages. 



In the very interesting report referred to above, 

 Frank Buckland quotes Dr. Letheby's chemical 

 analysis of the herring, in comparison with beef as a 

 food, and makes a calculation of its enormous value 

 to the population. According to Dr. Letheby's cal- 

 culation, beef contains 1,854 grs. carbon, and 184 grs. 

 nitrogen ; herrings, 1,435 grs. carbon, and 217 grs. 

 nitrogen. According to this, the herring is inferior to 



