AQUICULTURE 281 



ming larvae in summer (July), and these larvae, during the 

 days of their free existence, are carried in enormous numbers 

 by the outgoing tide down the runnels and streams which 

 converge towards the channel that opens to the Atlantic. 

 The first object of the oyster-farmer is to place artificial 

 " collectors " in the course of these streams, so as to inter- 

 cept the microscopic young oysters in that earliest stage, 

 and so save them from being carried out to sea and lost. 

 When the proper time comes, the oyster larva will settle 

 down for life by attaching itselE to any object which is firm 

 and clean — not slimy, like some sea-weeds. They have 

 been found elsewhere growing in numbers on the soles of 

 old boots, on the stems and bowls of old tobacco-pipes, and 

 on fragments of glass-ware and crockery. In natural 

 oyster-beds on the sea-bottom the young become attached 

 to the shells of the old oysters, to other dead shells, such 

 as those of cockles, and to any stones there may be in the 

 neighbourhood. On many oyster-beds, especially in Hol- 

 land, great quantities of old shells of oysters and cockles 

 are scattered over the ground as " cultch," for the young 

 " spat " to settle upon. But at Arcachon, and elsewhere 

 in France, special " collectors " are constructed and care- 

 fully placed in the best positions at the right time of year. 

 The simplest are merely bundles of twigs, or " fascines," 

 tied together and anchored with stones. The more usual 

 collectors are earthenware tiles, coated with a preparation 

 of lime and sand, so as to be clean and slightly rough, which 

 facilitates the attachment of the larva. Moreover, this 

 layer of whitewash forms a medium which can be cracked 

 off later on, when the young oyster has grown sufficiently 

 to be independent of support, and thus the tiles are left 

 intact, need not be broken up to free the oysters, and so 

 can be used as collectors year after year. The proportions 

 of lime and sand in the whitewash differ on different farms, 

 and so do the methods of arranging the tiles. They may 

 be stacked on the ground in open piles, so that the ebbing 



