ARTIFICIAL OYSTER CULTURE. 1085 



30,000 was as many as were ultimately realised. He could 

 not attribute that to any failure of the climate ; but he 

 believed it was due to inexperience and mismanagement. 

 In 1880, a large quantity of oysters were bred in ponds at 

 Newtown, in the Isle of Wight, and certainly, up to the 

 season of 1881, they were in a most excellent condition, 

 and if they had been properly cared for must have been 

 saved and brought to maturity ; but other matters inter- 

 fered which prevented their being so. He did not believe 

 there was any great difficulty in breeding oysters in ponds 

 in this conntry, except that they were really at the mercy 

 of the climate, because in shallow ponds the changes of 

 temperature were so rapid that the passage of a hail-storm 

 over it would utterly destroy the whole of the spat that 

 would be falling there. He had never thought it neces- 

 sary to aerate the water ; but let it in and out every day 

 with the tide. The state of the oyster, when in embryo, 

 would rather lead to the conclusion that in the day it 

 naturally floated to the surface towards the warmth of the 

 sun, and at night, when it was dark, sank to the ground ; 

 so that it was not difficult, by an arrangement of upper 

 and lower sluices, to arrange for a continual flow of fresh 

 water into the ponds. The greatest difficulty of all in 

 breeding oysters was the uncertainty of the fecundity of 

 the spat itself. He had seen ponds perfectly full of 

 spat, with every prospect of coming to maturity, and then 

 found in a short time that it had all disappeared. There 

 was a good deal of truth in what had been said about 

 the collectors. There was nothing to which oysters 

 would adhere in greater quantities than a smooth piece of 

 slate, so that actual roughness did not appear to be a neces- 

 sity ; what they heard most about was perfect cleanliness ; 

 if anything grew on the collectors when the oyster-spat 



