114 



PERILS OF EMBRYO LIFE. 



EGG THREE HOURS 

 AITER FERTILIZA- 

 TION. 



EGG AT A LATER STAGE. 



Nevertheless, a few escape and hatch out. Thereupon begins a series 

 of trials for the life of each embryo, so severe that it has scarcely one 

 chance in a million of surviving. 



These embryos, when first hatched, rise to the 

 surface of the water and swim there a few hours, 

 after which they begin to sink; and two or three 

 days may elapse before they are prepared to become 

 stationary. This is the period of their greatest peril. 

 Invisible motes, dancing a whirligig career just beneath 

 the surface, the gay young 

 oysters are endangered by the 

 open jaws of every marine 

 creature larger than them- 

 selves, and thousands may 

 sometimes perish in a single mouthful. 



They run a constant risk from the weather, 

 also. During his studj' of them on the Chesapeake, Dr. Brooks found 

 that any sudden cold wind, or a fall in the temperature, such as occurred 

 several times during his experiments (though made in mid- 

 summer), would kill every embryo in his care. How wide- 

 spread must be the destruction from such causes in the open 

 estuaries ! Of the ten million eggs shed by one parent, per- 

 haps half a dozen may survive to be graduated from this 

 play-day into the settling-down stage which begins the third 

 period of an oyster's life. How inscrutable would be this 

 fearful waste of potential life if we were compelled to think 

 of it as foreordered by the settled determination of a Crea- 

 tor's fiat — a scheme of reproduction unswayed and unswerv- 

 able by any altering circumstances, subsequent to its estab- 

 lishment in this world of incessant change ! 



Up to this point Nature has left the young oyster unshielded, so far 

 as can be seen. There is no protection for him whatever against the 

 liability to be destroyed — if, perchance, he ever succeeds in getting born ! — 

 not only through the voracity of a host, of marine animals, from sponges 

 up to the "leviathan," but also by comparatively slight changes in the air 

 or water. "We can fancy him quoting the melancholy old soliloquy, 



EGG IN ITS FI- 

 NAL STAGE. 



"If so soon I'm to be done for, 

 I wonder why I was begun for !" 



Nature has seemed to say, Let them go it ! I will provide so many that 



