I 1 62 OYSTERS, AND ALL ABOUT THEM. 



shown above, is complicated by many other circumstances, 

 some of which we have entered into in our chapter on deep- 

 sea cultivation. Velocity of tide, angle of dip of shore, 

 temperature and depth of water, arc amongst the most 

 important of these. 



BREEDING. 



The starting point of the oyster-breeder is obviously 

 the act of laying down mature oysters to spat. It might 

 appear to the superficial observer a very simple thing to 

 dredge up oysters from other beds and lay them down to 

 breed, but nothing is easier than to commit grave mistakes 

 at the outset. 



It used to be considered that oysters would not spat 

 after having been moved any distance, but the latest infor- 

 mation received on the subject leads us to think this 

 is an error. Removal may hinder, but need not prevent 

 subsequent fecundation. The after-health and well-doing 

 of the oyster depend in a great measure on the time of 

 year at which it is moved ; the best time being between 

 November and March, as it may be taken as a general rule 

 during the period of reproductiveness that, with one excep- 

 tion hereinafter mentioned, the longer the period between the 

 time that oysters are laid down and the time of their spatting, 

 the greater will the chances of reproduction be. Nothing can 

 be more injurious to the oyster than to move it whilst it is 

 sick, as, apart from the loss occasioned by the death of the 

 young about to be produced, the damage to the constitution 

 of the fish itself is so great as to make it improbable that 

 oysters so treated will ever spat again. It may seem extra- 

 ordinary to state after this that it has been lately found 

 advisable to place deep-sea oysters in breeding ponds as 

 short a time before spatting as can be arranged. The 

 reason for this may be that the difference in pressure 



