Image ID 113816 Premium Services      Northern Quahog (Mercenaria mercenaria) (top figure) and other bivalve mollusks Hand-colored lithograph, with outlines made by camera lucida, after J. W. Hill From: James Ellsworth DeKay, Zoology of New York, or the New York Fauna…. Vol. 1.5 of 5 (New York State. Geological Survey. Natural History of New York. Parts 1–6) (Albany, 1842–44) NYPL, Rare Books Division, Stuart Collection

The thick, strong shells of the widely abundant Quahog, or Round, or Hard-shelled Clam were made into beads called wampum by the native tribes of New Netherland. The purple part of the shell yielded the more desirable darker beads, which, like the white beads, were used both for ornament and as money by the Delaware Indians and the early colonists. The Quahog’s scientific name, Mercenaria mercenaria, doubly reflects its use as currency.

The animal within has long been a favorite American food item, whether eaten raw on the half-shell, incorporated into clam chowder (with or without tomatoes), or prepared in some other manner. Size designates it as a Littleneck, or Cherrystone, or Chowder clam. Until the early 20th century, when polluted waters ended this industry, New York City clams were widely exported to other American cities. In recent years, as the city’s waters have become cleaner, local clams have begun once again to be harvested and eaten, surreptitiously, in defiance of local health laws.

Included with the illustration of the Quahog in DeKay’s landmark study of the fauna of New York State are several other local mollusks, including the Gem Clam, Gemma gemma (bottom figure), from the East River, and then known as "Venus gemma."