MOLLUSKS AND CRUSTACEANS 



349 



The oyster industry is very profitable. Hundreds of boats and 

 thousands of men are engaged in dredging for oysters. Three 

 of the most important of our oyster grounds are Long Island 

 Sound, Narragansett Bay, and Chesapeake Bay. 



Sometimes oysters are artificially '^ fattened " by placing them 

 near the mouths of fresh-water streams. Too often these streams 

 are the bearers of sewage, and the oyster, which lives on micro- 

 scopic organisms, takes in a number of bacteria with other food. 

 Thus a person might become infected with the typhoid bacillus 

 by eating raw oysters. State and city supervision of the oyster 

 industry now makes this possibility very much less than it was some 



Oyster, clam, and scallop. 



years ago, as careful bacteriological analysis of the surrounding 

 water is constantly made by competent experts. 



Clams. — Other bivalve mollusks used for food are clams and 

 scallops. Two species of the former are known to New Yorkers, 

 one as the '^ round," another as the " long " or " soft-shelled " 

 clam. The former (Venus mercenaria) was called by the Indians 

 *' quahog," and is still so called in the Eastern states. The blue 

 area of its shell was used by the Indians to make wampum, or 

 money. The quahog is now extensively used as food. The 

 '' long " clam {My a arenaria) is considered better eating by the 

 inhabitants of Massachusetts and Rhode Island. This clam was 

 highly prized as food by the Indians. Dredging for scallops, 

 another molluscan delicacy, is an important industry along certain 

 parts of the eastern coast. 



Crustaceans as Food. — Crustaceans are of considerable value 

 for food. The lobster is highly esteemed as food but has become 

 scarce as the result of overfishing. Laws have been enacted in most 

 lobster-producing states against overfishing. Egg-carrying lob- 



