674 



MARINE PRODUCTS OF COMMERCE 



Table 150. Production of Sea Mussels by States, 1945. 



Total 3,308,900 



Source: U. S. Fish and Wildlife Service. 



$181,226 



stakes than on the mud of the flats. He therefore constructed a double hedge of 

 stakes along the low-tide mark which offered a large surface for the growth of 

 mussels. 



Species Utilized. Two important species of mussels are found on the North 

 American Coast; Mytilis edulis, Linnaeus, occurs on the Atlantic Coast as far south 

 as North Carolina, while this species and a closely related species, Mytilis californi- 

 anus, Conrad, are found on the Pacific Coast from Alaska to San Francisco. The 



(Courtesy U, S. Fisli and Wildlife Service) 



Fig. 32-3. The sea mussel ( Mytilis edulis ) . 



latter when full grown is much larger and has a rougher shell than Mytilis edulis. 



The favorite habitat of these mussels is at the low-tide mark in slightly brackish 

 water, along swift tide ways, and in protected bays and estuaries. Mussels often 

 attach themselves to the piles and timbers of bridges, wharves, and to other 

 objects, such as rocks and buoys. 



The internal structure of mussels bears a general resemblance to that of the 

 clam and many other bivalves. The mussel is characterized by the small, strong, 

 triangular foot, and especially by the strong and prominent byssus or "beard." The 

 byssus enables the mussel to attach itself firmly to the shell of another mussel, 

 or to a rock or some other object. A viscous liquid is excreted by glands, which 



