SUPPLEMENT. I2Oy 



only ten per cent, of the oysters were found to be white or 

 black-sick. We think that these conclusions were hastily 

 arrived at, for the reason before mentioned, that oysters do 

 not breed exactly at the same time. Mr. Buckland examined 

 a bed in 1875, and, we think, he stated that he found one 

 in six spatting. 



Deep-sea oysters appear to spat earlier in shallow water 

 than at a greater depth. Oysters in eight fathoms of water 

 have been know to spat fourteen days earlier than those in 

 eighteen fathoms of water. 



The time of spatting is entirely dependent on local 

 conditions, such as temperature, warm currents, and general 

 climatic influences. Currents which affect one part of a 

 bed may not affect another part only a few hundred feet 

 distant. 



In 1878 an oyster was found at Whitstable, white-sick, 

 on the 1 7th of June, and the same oyster was black-sick 

 ten days later, the temperature of the water being at that 

 time from 58 to 60 degrees (Faht). 



Oysters have been known to spat as late as October, 

 and even November, during a mild season, but in these 

 cases it is exceedingly improbably that any of their progeny 

 survived. 



Thus it is seen that oysters breed all through the warm 

 months, though the time at which the spat falls depends 

 as much on the temperature during April and May as 

 through the later months. 



The internal development of germs commences in one 

 or other of these two months, and although the ist of May 

 is the date fixed by custom for the prohibition of the sale 

 of oysters, they may or may not be fit to eat at any time 

 of the year between the ist of April and the ist of 

 November. 



