174 UTILIZATION OF MINUTE LIFE. 



To these the young oysters attach themselves ; and 

 so fruitful were the results, that one of the fascines 

 that was examined at the expiration of six months, 

 was found to have no less than 20,000 young 

 oysters upon it (Fig. 20). 



A report furnished to the French Government 

 shows that about twenty-five thousand acres of coast 

 may be brought into full bearing in three years, at 

 an annual expense not exceeding 400. 



But to ensure the continuous propagation of 

 artificially-formed oyster-beds, the dredging must 

 be effected at proper intervals.* For this purpose 

 the beds must be divided into zones, and one-third 

 of each zone only be dredged each season. In this 

 manner an absolute repose of two years is allowed 

 to each of the zones. 



Hitherto, the dredging used to take place in 

 September, the spawning season being then over ; 

 but in that very month the young oysters attach 

 themselves to their parents' shells, so that the 

 mollusca are disturbed at a moment when the new 

 population is beginning to form. To avoid this, 

 M. Coste has proposed to fix the dredging season 

 in February or March. 



In England there have been many Acts of 

 Parliament passed for the protection of oyster- 



* Dredging is performed with a strong net, having an iron rod 

 at its base. 



