When selected for the table, lobsters ought to be heavy in proportion to their size, and to have a hard, and firm crust. During winter the male lobsters are generally preferred for the table. These are distinguished by the narrowness of their tail, and by the first two fins beneath being large and hard. The females, on the contrary, are broader in the tail, and have these fins small and soft. The roe or eggs are found under the tail of the females for some time after they have been protruded from the body, and in this state the females are generally preferred to the males. When fresh, the tails of lobsters are stiff, and pull open with a spring, but when they are stale the joints of the tail become flaccid. 266. _The SEA CRAW-FISH, or SPINY LOBSTER_ (Cancer homarus), _is a crustaceous animal, distinguishable from the common lobster, by its shell being covered with spines, mud by each of the legs ending in a hairy claw._ _This species is of large size, and is found in most of the European seas._ Sea craw-fish are very common in the London markets, where they are sold at a price inferior to that of the common lobsters. Their flesh is hard, and has a peculiar sweetness, which by many persons is much disliked. At Marseilles, and on the coast of the Mediterranean, however, they are in considerable request on account of their eggs, which are esteemed a great delicacy. These begin to appear towards the end of May, and are cast about two months afterwards. 267. _The COMMON, or FRESH-WATER CRAW-FISH_ (Cancer astacus), _is a small crustaceous animal, in shape somewhat resembling a lobster, and distinguished by having its large claws beset with numerous tubercles, and the beak between its eyes being toothed on each side, and having a single tooth at the base._ _It inhabits holes in the clayey or stony banks of many of the rivers of England, and is seldom known to exceed the length of three or four inches._ Craw-fish are frequently used in cookery; and their flesh is considered nutritive, but somewhat indigestible. Those substances which in medicine are improperly denominated _crabs' eyes_ are concretions formed within the thorax of the craw-fish. They are generally about the size of peas, or larger, somewhat flatted on one side, and of whitish colour. The principal part of them are brought from Muscovy, and particularly from the banks of the river Don. In England the usual mode of catching craw-fish is by cleft sticks, baited with flesh or garbage, and stuck in the mud near their haunts at the distance of a few feet from each other. After being suffered to remain some time, these are gently drawn up, and a basket is put under them to receive the animals, which always drop off as soon as they are brought to the surface of the water.