On Food and Cooking

“siphons,” one for inhaling and the other for
exhaling, which may be separate or else
joined together into a single “neck.”
The U.S. term “hard shell” is applied to
sturdy clams that close completely (little-
neck, quahog), while “soft shell” clams have
siphons much longer than the shell, which is
thin and always gapes (steamer, longneck).
The Japanese or Manila hard-shell clam
(Ruditapes philippinarum) is the only one to
be cultivated on a large scale worldwide,
thanks to its robustness and preference for
shallow burial. The other dozen or so common
clam species are mainly regional products.
Some species of the large surf clam
(Mactromeris species) absorb plankton
pigments and have a striking red layer on
several muscles. The largest and most
grotesque of the temperate commercial clams
is the deep-burrowing geoduck of the Pacific
Northwest subtidal mudflats (Panope
generosa), whose neck looks like a small