^C. vulgaris^, the common sand-shrimp. It ranges from Labrador to North Carolina on the Atlantic coast and from Alaska to southern California on the Pacific coast. It is found in abundance on sandy shores at low-water mark, and in shallow water below tide-mark; also among rocks and seaweeds. When left by the tide it buries itself in the sand. Its color varies with its location, rendering it inconspicuous. Upon the [pg261] sandy shores it is translucent, pale in color, and often specked, closely resembling the sand, while on dark, muddy bottoms it is much darker. This is an edible shrimp, eagerly devoured by fishes; it is also gathered for the markets. The body of /C. vulgaris/ is broad at the anterior end and tapers to a sharp point at the posterior extremity. A pair of broad, divided appendages on the cylindrical segment, which is next to the last on the abdomen, together with the sharp telson, form a fan-like swimming-tail. As in all shrimps, the antennæ are long and have plate-like antennal scales at the base, which are fringed with hairs. The mandibles are long. The movable finger of the chela is folded across the extremity of the claw. ^C. franciscorum^, the California shrimp. This species is about three inches in length. It is distinguished from /C. vulgaris/ by its larger size and by the greater length of the movable finger of the chela, which folds parallel to the side of the claw instead of across its extremity. Its color is light or dark yellowish-gray, mottled. This is the shrimp extensively gathered by the Chinese for commercial purposes. The shrimp-meat is dried and cured, and then separated by blowers very much as wheat is cleaned. It is exported to Eastern countries in great quantities, the value of the export being estimated at one hundred thousand dollars per annum. [Illustration: /Crangon vulgaris/, the common sand-shrimp; male, natural size.] CREEPING FORMS: LOBSTERS AND CRAWFISH FAMILY ~ASTACOIDÆ~ GENUS ^Homarus^ There are but three species of this genus, which is the most important one of all the /Crustacea/. They are /H. vulgaris/ of Europe, /H. capensis/ of the Cape of Good Hope, and /H. americanus/, which occurs on the eastern coast of the United States from Labrador to New Jersey. The lobster-fishery is one of great importance, and of such value that it is governed by stringent laws. The [pg262] annual catch on the Atlantic coast of North America amounts to many millions of lobsters, the money value of which is very large.