66 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [360] 
more or less mottled and streaked with dark brown, and sometimes with 
opaque white. 
This species is taken in large quantities for food, and may almost al- 
ways be seen of various sizes in our markets. The small or moderate- 
sized ones are generally preferred to the full-grown clams. Most of 
those sold come from the muddy estuaries, in shallow water, and are 
fished up chiefly by means of long tongs and rakes, such as are often used 
for obtaining oysters. Sometimes they are dredged, and occasionally 
they can be obtained by hand at or just below low-water mark. These 
estuary specimens usually have rough, thick, dull-white, or mud-stained 
shells, but those from the sandy shores outside have thinner and more 
delicate shells, often with high, thin ribs, especially when young; and 
in some varieties the shell is handsomely marked with angular or zig- 
zag lines or streaks of red or brown, (var. notata.) These varieties 
often appear so different from the ordinazy estuary shells that many 
writers have described them as distinct species, but intermediate styles 
also occur. This species is very abundant along the coast from Cape 
Cod to Florida; north of Cape Cod it is comparatively rare and local: 
It does not occur on the coast of Maine or in the Bay of Fundy, except 
in a few special localities, in small, sheltered bays, where the water is 
shallow and warm, as at Quahog Bay, near Portland; but in the south- 
ern parts of the Gulf of Saint Lawrence, as about Prince Edward’s 
_ Island and the opposite coast of Nova Scotia, where the water is shal- 
low and much warmer than on the coast of Maine, this species again 
occurs in some abundance, associated, in the same waters, with the 
oyster and many other southern species that are also absent from the 
northern coasts of New England, aud constituting a genuine southern 
colony, surrounded on all sides, both north and south, by the boreal 
fauna. 
The curious and delicate shell called Solenomya velum (Plate XXIX, 
fig. 210) is occasionally found burrowing in the pure, fine, siliceous sand 
near low-water mark, about two inches below the surface, but its proper 
home is in shallow water, beyond low-water mark, and it is, perhaps 
most abundant where there is mud mixed with sand, and it also lives 
in soft mud. Its shell is glossy and of a beautiful brown color, and is 
very thin, flexible, and almost parchment-like in texture, especially at 
the edges. It is avery active species, and has a very curious foot, 
which is protruded from the front end of the shell, and can be used in 
burrowing, very much asthe “ razor-shell,” described above, uses its foot; 
but the Solenomya makes use of its foot in another way, for it can swim 
quite rapidly through the water, leaving the bottom entirely, by means 
of the same organ. The foot can be expanded into a concave disk or 
umbrella-like form at the end, and, by suddenly protruding the foot 
and expanding it at the same time, a backward motion is obtained by 
the reaction against the water; or, by suddenly withdrawing the foot 
and allowing it to remain expanded during most of the stroke, a for- 
