180 



SEA-SHORE LIFE 



Fig. 50; EDIBLE MUSSEL. Cape 

 Ann, Mass. 



iiig tlie foot upwards, and attaching themselves successively 

 higher and higher up by means of newly formed byssus threads. 

 When the tide is high the valves of the mussels will be seen to 



be gaping, and the beautifully 

 .. fringed edges of their mantles 



protruding slightly, allowing 



water and minute organisms to be 



^ drawn into their gill cavities, and 



from thence into their mouths at 

 the opposite end of the shell. 

 There are two adductor muscles 

 instead of one, as in the oyster, 

 but in most respects the anatomy 

 of the mussel closely approaches that of the oyster. In France the 

 mussels are cultivated and highly esteemed as food, and the fishery 

 is worth more than f 150,000 annually. We make very little use 

 of our mussels, as at times they are said to be more or less poison- 

 ous; especially those found growing upon wood. An account of 

 the development of the edible mussel is given by John Wilson in 

 "Fifth Annual Re- 

 port of the Fishery 

 Board for S c o t - 

 land," for 1886. 



The Ribbed 

 Mussel , ( Modiola 

 plieatida, Fig. 91J, 

 can be disting- 

 uished by the radi- 

 ating ridges of the 

 shell. It is a brack- 

 ish water sjiecies 

 and is found between tide limits from Nova Scotia to Georgia. 

 •■■•■ The Horse Mussel, or Bearded Mussel, f Modiola modiolus, Fig. 

 94), lives half buried in gravelly bottoms, or firmly attached by its 

 byssus threads within crevices of rocks, below low-tide level. It 

 ranges from New Jersey to the Arctic Ocean, and the northern 

 coasts of Europe. It is chestnut brown, and the skin flakes off 

 around the edges of the shell, forming a shaggy yellow "beard." 



■■'An illustration of the Horse Mussel with scale limpets and egg cocoons of Kock Snail, on 

 page 1^48. 



Fig. gi; EIBHED MUSSEL. 



