THE OYSTER. 79 



the Investigation of Oyster Fisheries, in May, 1876, 

 there were in the harbor of Emsworth, between the 

 years of 1840 and 1850, so many oysters that one man 

 in five hours could take from 24,000 to 32,000. In 

 consequence of over-fishing, in 1858 scarcely ten ves- 

 sels could find loads, and in 1868 a dredger in five 

 hours could not find more than twenty oysters. 



The oyster fisheries of Jersey, in the English Chan- 

 nel, at one time afforded employment to 400 vessels. 

 In six or seven years the dredging became so exten- 

 sive and the beds so exhausted that only three or four 

 vessels could find employment, and the crews of even 

 that small number had to do additional work on shore 

 in order to support themselves. 



In view of such facts as these, no one who appreci- 

 ates the magnitude of the oyster industry of the 

 Chesapeake Bay can doubt that the protection of our 

 beds is a matter of vital importance, for it is quite 

 clear that we cannot trust to the natural fecundity of 

 the oyster. 



It is well known to naturalists that the number of 

 individuals which reach maturity in any species of 

 animal or plant does not depend on the number which 

 are born. The common tapeworm lays hundreds of 

 millions of eggs in a very short time, yet it is com- 

 paratively rare. The number of children born to each 

 pair of human beings during their lifetime of sixty or 

 seventy years can be counted on the fingers, yet man 

 is the most abundant of the large mammals. The 

 abundance of a species is mainly determined by the ex- 



