448 MARINE INVERTEBRATES 
of comestible species. Several of its genera have been named 
after various goddesses and nymphs on account of the great 
beauty of their shells. But from a purely biological point of 
view also the Veneride have claims to distinction, for they seem 
to represent about the highest type of shell-development among 
the bivalves. The test is extremely hard and often porcelanous. 
It is solid without being ponderous and unwieldy in the sense of 
causing the animal to be helplessly overburdened by the sheer 
weight of its shell. The valves are equal and have three 
stout cardinal teeth. The foot is strong, the animal is active, 
the siphons are free or partially united, and the gills are more or 
less crumpled andfolded. There is a compactness and well-regu- 
lated arrangement of the organs in the Veneridw, which impress 
one who has examined the anatomy of many pelecypods much 
as a well-built, efficient, and space-economizing machine would 
impress a mechanic. None of the organs are weak or crowded 
out to furnish room for the undue or awkward development of 
other organs. A good balance is preserved between them all, 
the result being a high type of pelecypod. 
If we do not expect to find any of the more remarkable forms 
of the Veneridw upon our shores we shall be the less disappointed 
when returning from collecting-expeditions. Nevertheless, there 
are a few species of Cytherea, Dosinia, and Tivela in North Ameri- 
can waters which are very handsome shells; but those of our 
species which are included under the generic name Venus are in 
point of beauty not worthy of their promising name. 
Genus Venus 
V. mercenaria. This is the common “hard-shell clam,” the “ Lit- 
tle Neck ” of the hotels and restaurants, with which every one in New York 
and New England is familiar. The species ranges from Cape Cod to 
Florida, and occupies two different kinds of station: one in shallow 
muddy bays near low-tide mark, in estuaries, etc.; the other the sandy 
stations in open deeper bays or the open ocean. Those coming from 
outside ” have thinner, more delicate shells, with thin, concentric ribs. 
They burrow in the sand or mud, or crawl quite rapidly. The siphons 
are short and are united almost to their ends. The mantle is open (save 
for the siphons), and the edges are delicately frilled. In the United 
States this species is very extensively gathered for the markets. When 
the oyster season closes in April, the hard-shell clam comes into vogue, 
the season lasting until September or October. The clams are exten- 
