THE OYSTER. 



numerous at some points than at others, and for this 

 reason the fluid has a cloudy or curdled appearance. 

 By selecting a place where the granules are few and 

 pretty well scattered, very careful watching will show 

 that each of them has a lively, dancing motion ; and 

 examination with a power of 500 diameters will show 

 that each of them is tadpole-shaped, and consists of a 

 small oval, sharply defined ' head," and a long, deli- 

 cate " tail," by the lashing of which the dancing is pro- 

 duced. These are the male cells, whose union with the 

 eggs or ova of the female is necessary to the fertiliza- 

 tion of the latter, and the consequent hatching of living 

 oysters. 



The number of male cells which a single male will 

 yield is great beyond all power of expression, but the 

 number of eggs which an average female will furnish 

 may be estimated with sufficient exactness. An un- 

 usually large American oyster will yield nearly a 

 cubic inch of eggs, and if these were all in absolute 

 contact with each other, and there were no portions of 

 the ovaries or other organs mixed with them, the 

 cubic inch would contain 5OO 3 , or 125,000,000. Di- 

 viding this by two, to allow for foreign matter, inter- 

 spaces and errors of measurement, we have about 

 60,000,000 as the possible number of eggs from a single 

 very large oyster. 



In another place I have shown that, by mixing eggs 

 extracted from a female with male cells, it is an easy 

 matter to secure their union in a watch crystal or in a 

 glass beaker. 



