266 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



the most important beiug in Chesapeake Bay, mainly upon the natural 

 beds, and in Long Island Sound, principally upon planted grounds. 

 The Canadian oyster-beds are much depleted, and an eiibrt is now 

 being made to restore them to a productive condition. 



PACIFIC COAST. 



Uj)on the western coast of North America there are five, and perhaps 

 six, recognized species of oysters, but only two of them are of present 

 importance. 



The eastern oyster was jilanted in San Francisco Bay about 1872 and 

 has there formed the basis of a somewhat important industry ever 

 since. The supply has been maintained by the annual plantmg of seed 

 oysters from the east, and while the species ajjpears to be propagating 

 itself to a limited extent, no reliance has been placed upon this fact 

 for the maintenance of the beds. The United States Fish Commission 

 has recently planted oysters in Willapa Bay, Washington 5 Yaquina 

 Bay, Oregon, and Humboldt Bay, California, but it is still too early to 

 say with what success. 



The native oyster {Ostrea lurida) of California, Oregon, and Washing- 

 ton is found at various i)laces on the coasts of the States mentioned, 

 but attains its greatest size and perfection in Willapa Bay. It is much 

 inferior to the eastern oyster in size, but its flavor is esteemed by many. 



In the Gull of California is found a large species, Ostrea iridescens, 

 which resembles the eastern species and is an object of some trade in 

 the adjoining portions of Mexico. Attempts have been made to intro- 

 duce this form in the markets of San Francisco, but the mortality en 

 route has been large and the venture unprofitable. 



Two smaller oysters, Ostrea palumea and Ostrea ])alumea glomerata, 

 are also found in the Gulf of California. 



DESCRIPTION. 

 EASTERN OYSTER, OSTREA VIRGINIANA. 



The shell of this species is generally elongate, but varies much with 

 age and the conditions under which it grows. In the younger stages it 

 is often nearly round, with ear-like projections on each side of the 

 hinge and stout radiating ridges near the margin, thus bearing some 

 resemblance to the European oyster. In shells which are actively 

 growing there is a broad fringe of yellow cuticle around the edge of the 

 valves, which, however, soon becomes thickened by a deposit of lime. 



The shell is subject to great variation in thickness, but it is rarely 

 so thin as in the Pacific coast oyster. The exterior is marked by 

 laminations and more or less concentric lines of growth; it is often 

 covered by a yellowish cuticle, but is sometimes white and flinty in 

 appearance. The inside of the shell is generally white, somewhat 

 tinged with purple near the margins, and with a more or less pearly 

 luster. The muscular impression is generally nearer to the j^osterior 



