238 BULLETIN. OF THE BUREAU OF FISHERIES. 



which they can rise and fall by means of a floating axis. The grooved stakes are 

 mounted with a crosstree bearing a ring on the underside. The frame is surmounted 

 with a hook so that it can be raised from the water and hung on the ring of the crosstree 

 above (fig. 223, opp. p. 236). With this device the mussel culturist can at any time 

 gather, replenish, wash, or do any necessary work at his convenience, and when through, 

 return the frame to the water. 



The capacity of one of these claies is about 10,000 mussels, weighing from 660 to 

 880 pounds. The young mussels are collected on the shores of Berre Lake and placed 

 on the claies by the same method employed in fixing seed mussels to bouchots. When 

 of sufficient size they are marketed without any further transplanting. 



Still another means for collecting spat and rearing mussels is by means of the raft 

 collector (fig. 222, opp. p. 236) recommended by Fraiche (1863). It consists of a raft 

 from which hang planks or frames in a vertical position. It is anchored in a region 

 where mussels are spawning and when covered with spat is towed to a breeding basin 

 where the rearing can take place without any further care than to see that no mud 

 accumulates on the frames. The chief objection to this contrivance is that the planks 

 or frames decay rapidly, often causing an entire loss of the harvest. This difficulty can 

 not be remedied, as some have thought, by replacing the wood with metal, because 

 spawn will not set on it. 



Myticulture is also practiced in Italy, especially in the vicinity of Taranto, where 

 mussels are raised to supply the southern markets of the peninsula as far north as Rome. 

 Here the shellfish are cultivated on ropes made from rushes or "alfa" suspended in the 

 water from stakes, which are placed from 20 to 30 feet apart, depending on the depth of 

 the water. The ropes are hung over the mussel beds close to the shellfish in order to 

 catch the free-swimming young. Six months after a set of spat has occurred the ropes 

 are taken up and all the shellfish on them which have attained the size of an almond 

 are removed. The smaller ones are left to grow until the following season, when they 

 will have attained sufficient size for food purposes. The larger mussels selected are 

 interlaced, either singly or in bunches, into ropes which are then suspended vertically 

 in the water from a main rope extending between two stakes planted out in deep water. 

 Parks are also utilized in the culture of mussels by this means, «ome of them extending 

 2,600 to 2,925 feet into the sea. Bouchon-Brandely (1883) states that the yearly yield 

 of such a park is 40,000 to 50,000 pounds, worth from $880 to $1,100. 



In Germany the Bay of Kiel contains extensive areas where mussels are raised by 

 artificial means. The method employed there is to drive stakes into the bottom and 

 leave them there for a period of three to five years, during which time they become 

 covered with mussels of marketable size. They are then taken up, stripped of the 

 shellfish, and replaced by others. About 1,000 stakes are planted annually in this 

 locality, from which the yield of mussels amounts to about 800 tons. 



The systems of myticulture which have been described above are especially adapted 

 for regions where the bottom is composed of mud too soft to support a bed of mussels 

 and where there is considerable rise and fall of tide over large areas. Where the bottom 

 is hard or covered with only a thin layer of mud and where silt is not being deposited 

 too rapidly, a much more economical method of cultivation is merely to transplant the 

 mussels from crowded situations to more extensive areas where food is abundant. It 

 is in this manner that mussels are grown for market in England and for that reason it 



