NATURAL HISTORY OF THE MUSSEL" 55 



between tide marks, it is also capable of thriving 

 perfectly at some distance from the shore, and 

 in fairly deep water. The Government beds of 

 Holland, for instance, which are hired out to 

 culturists, are usually laid down where the water 

 is a depth of from 7 to 15 feet at low tide. 

 These mussels grow commonly to a length of 2 

 or 2J inches. They are therefore of excellent 

 size, and are much used as food both in Holland 

 and in France. Some of the beds at Lynn and 

 Boston also are constantly covered by water. 

 The Skibo beds of Meikle Ferry, Sutherlandshire, 

 are mostly covered by 10 or 15 feet at low-water 

 springs, and in almost all the estuaries of our 

 larger rivers the channels contain mussel beds of 

 greater or less extent. 



The favourite position of the mussel, however, 

 if such an expression is allowable, may be said to 

 be a few feet above the level of low-water mark, 

 if there is a considerable rise and fall of tide ; or 

 between the low levels of spring and neap tides. 

 In this position the rate of growth will be more 

 rapid than is possible when the mussel is high 

 above low water, and exposed to the air for long 

 periods. The feeding and environment of dif- 

 ferent localities largely determine what the rate 



