364 THE ZOOLOGIST. 





depth of water. Allowing one yard for the dip of the horizontal 

 rope at its centre under the weight of the Oysters, and another 

 yard as the distance the end of the pendant should be from the 

 bottom, the length of rope for 18 ft. of water would be about 

 12 ft. ; for 30 ft. of water about 24 ft., and so on. The pergolari 

 are usually set about one yard apart ; if closer, the Oysters do 

 not develop so rapidly. 



As will be easily understood, many Oysters, during the above 

 operation, become detached from the fascines. Loose Oysters, 

 so detached, are laid side by side, base or joint upwards, in a flat 

 open basket. Over them is scattered a layer of one-year-old 

 Mussels ; the basket with its mixed contents is then hung on to 

 the palisade. Eight or nine days suffice for the Mussels to 

 attach themselves to the Oysters and to one another. The 

 baskets are then withdrawn, and handfuls of the united Oysters 

 and Mussels are worked up between the strands of rope, and form 

 mixed pergolari. These are first hung horizontally (a radicola) 

 by tying the ends to the two opposite ropes of a camera. In this 

 way the strands hold tighter, and the shells are less likely to 

 drop. After a few days the Mussels adhere to the rope, and the 

 pergolari can then be hung vertically. 



As the Oysters grow, overcrowding is avoided by remaking 

 the pergolari. This takes place in December. The sprigs with 

 the larger Oysters are collected and remade into separate pen- 

 dants; those with smaller shells are sorted out and reset; whilst 

 a few Oysters {a cunichiella) are formed into a third set of pen- 

 dants. A cunichiella is a name given to such Oysters as have 

 grown opposite each other on the same sprig, and are therefore 

 attached together only by a small portion of wood at the base of 

 the shell. Such pairs are cut off and inserted between the rope 

 strands, and are reckoned to produce the finest class of Oysters. 

 Loose Oysters are treated with Mussels as before. The mixed 

 pergolari require a weeding out of the Mussels to give the 

 Oysters greater space for development. 



At the beginning of the following summer some of the Oysters 

 are so far grown as to be ready for sale. These are detached, 

 and in numbers of 300 to 400 are placed in the nassa, a wicker 

 basket, in which they can be quickly drawn from the water 

 for sale. 



By this system of culture a good part of the Oysters can be 



