A land representative of a numerous marine group.
Shrimps and Prawns are red when cooked, but when alive are very pretty semi-transparent objects, which may be seen swimming about through the glass of aquariums placed against the wall. Prawns are larger than shrimps, and have a strong serrated spine in front of the head. Shrimps and prawns, of which several kinds are found off the British coasts, generally prefer shallow water, with a sandy bottom. In most of these the first two pairs of feet are divided to form a pair of pincers at the extremity; but in such small creatures this is easily overlooked, unless special attention is directed to it. It is different with the Lobsters and Crayfish, which much resemble shrimps in form, but are very much larger, and armed with a pair of very large pincer-like claws, in addition to the other legs. Lobsters live in the sea, in holes in the rocks, into which they dart backwards, and there protect themselves with only the head and claws projecting at the opening, ready to face any intruder. Crayfish, which are smaller, live in holes in the banks of brooks and rivers. There are many species, some of large size and bright colours. The Common Lobster is black when living, but other species are red, blue, or variegated.
Photo by W. P. Dando, F.Z.S.] [Regent's Park.
SHRIMP.
A species which plays an important part in the food-supply of London.
Sometimes, if we pick up a whelk-shell on the beach, we shall find it inhabited, not by a mollusc, but by a crab, with its legs and claws wedged together, so as to fill the aperture completely—one claw, much larger than the other, resting in front; and if we pull it out, we shall find that, though the front of its body and the legs and claws are hard, like those of an ordinary crab, it has a long, soft, fleshy tail, absolutely defenceless and unprotected. Crabs belonging to this curious section are called Hermit-crabs, and protect themselves by taking possession of shells which they have either found empty or appropriated by the easy and economical process of devouring the owners. The few species found on the British coasts are all small, and more frequently noticed in whelk-shells than in any others; but tropical species attain to a considerable size, and may sometimes be found in shells measuring 3 or 4 inches across at the opening.
Photo by C. N. Mavroyeni] [Smyrna.
FRESH-WATER CRAB.