68 SHELL-FISH COMMISSIONERS’ REPORT. [Jan., 
tions of Dr. W. K. Brooks of Johns Hopkins University, 
there can be no question that, as regards the Virginia 
oysters, and probably all the American oysters, they are 
bi-sexual, the fluid of the male being readily distin- 
guished from that of the female. The ova, after being 
ejected from the female, meets the sperm of the male as it 
floats in the water, and is there fecundated. Within two 
hours after this union, the young oyster starts on his brief 
journey through the water, drifting at the mercy of the 
currents. He is microscopic in size, but after two weeks’ 
buffeting he grows large enough to be seen by the naked 
eye. 
The brood oyster of the Atlantic coast is enormously pro- 
lific; the estimates vary from nine millions to sixty mil- 
lions of eggs from a full-sized spawner. The eggs are 
smaller than those of the European species, but they are 
far more numerous. 
A sudden fall of the temperature or a heavy storm 
checks spawning, and often kills the spawn; warm, pleasant 
weather is favorable to both. 
Many European naturalists say that oysters do not spawn 
until they are three years old, and then not every year. 
How often they spawn cannot be easily determined, 
but it is a fact well established that Connecticut yearling 
oysters frequently spawn; but the quantity spawned is 
much less than that of older oysters. 
It is estimated that the larger portion of the ova cast is 
lost through failure of fecundation. The rest, the smaller 
but more fortunate portion, during their drifting period, 
being still exposed to many dangers, dwindle rapidly away. 
Many are eaten up by fish and other creatures of the water, 
many are drifted into colder currents and are chilled to 
death; many fall upon muddy bottoms and are suflocated ; 
and many are washed ashore, to be dried up by the sun 
and air. When finally the survivors fall upon a suitable 
“stool” they adhere to it with great tenacity, and their 
chances of life are much improved. But they are not yet 
out of danger; as long as their shells are thin and delicate 
they afford but little protection against hostile attack. 
