BIVALVE MOLLUSCA. 391 
captive in the protected basins, where they are sheltered from various 
causes of destruction to which oysters are exposed in the open sea. 
Upon the bottom of the lake, and all around it, the proprietors ot 
Fusaro have here and there constructed hillocks, with stones heaped 
up, and artificial rocks, raised sufficiently to shelter the depéts from 
mud and slime. Upon these rocks they deposit the young oysters 
gathered in the Gulf of Tarentum, Each of these rock-works is sur- 
rounded by a girdle of piles, driven close to each other, and raised a 
Pillars with cords attached in Lake Fusaro. 
Fig. 173 
little above the surface of the water, as represented in Fig. 172. 
Other piles are distributed in long lines, and bound to each other by 
a cord, from which are suspended fagots of young wood. In the 
spawning season the oysters which have been deposited on the arti- 
ficial rocks discharge the myriads of young fry which have been 
nurtured ‘in the folds of their mantles. The fagots suspended from 
the piles arrest the fry before they are driven away by the waves. 
By these precautions the proprietors of Fusaro have provided for the 
preservation of the young fry, besides removing many of the natural 
enemies of the young oyster. : 
In other places the piles are distributed in long lines and bound 
together by strong cords, from which fagots of brushwood are sus- 
pended, on which the young spawn lay hold, as in Fig. 173. 
