Several small crabs are destructive to the grow ing grain crops of the tropics. The rice plant grown on the Mullis at the mouth of the Indus, is much cut down by a small black sea crab, called by the people Kookee. Without any apparent object, it cuts down the growing grain in largo quantities, and often occasions much loss.
The Land Crabs are. migratory, and often take long journeys. They live in the interstices of rocks, in the clefts of trees, and bore holes in the ground.
The Eriocheir Japonicus of Manchuria is re markable for its liahy. hand. A curious little crab of the Malacca Straits has been called by 31r. Bate, Sphmrapceia Collingivoodii, because of its taking in sand to eliminate its food, and eject ing the sand in the form of a pill. The species is gregarious. The Phyllosoma are styled Glass Crabs. The large Spider Crab of the Japanese islands . Inachus Kminpferi, has been measured llf feet from tip to tip. It is of a bright yellow, with crimson patches.
The Ocypode ceratopbthalmus of Ceylon bur rows in the dry soil, jerking out the sand to a distance of seven feet. Of the Painted Crabs, the Crabes peintes and Crabes violets of the French, Grapsus strigosus, Herbst., is distinguished by dark red marks on a yellow ground. They aro found on the reef to the south of Colombo harbour. The Paddling Cmbs, Neptunus pelagicus, Linn., and N. sanguinolentns, Herbst., have their hind pair of legs terminated by flattened plates, to assist them in swimming.
The larvm of the crab are termed Zoem. The crab has periodic moultings, during which it escapes from its shell a soft, harmless creature, incapable of exertion or resistance and would become an easy prey to any of the 'devourers so numerous in the sea, were it not that so soon a.5
the denudation is complete, a, stout crab of the same species takes care of it to the best of its ability, until a new shelly case grow, and it is enabled again to protect itself, and present a stroll°. back to its foe. If the sentinel be removed, another will be found to have taken its place after the next tide, and this will be repeated many times in succession. While the crabs are young, the change of shell is supposed to take place frequently, and there is probably a time when the changes cease. Crabs and other crustacea aro said to cast away their limbs when alarmed or frightened, as on the occasion of a thunderstorm, or on the firing of a cannon, and this is believed to be true. When a, claw has sustained any injury, it is cast off by the animal, and a new ono in due time takes its place. 3fost land crabs are carrion feeders ; a few are vegetarians. Swimming crabs, Poly bins species, are mostly predacious.
The place of the crabs amongst the crustacem is well defined.
Latreille, Desmarcst, Leach, the two 3filne Edwards, Do Haan, Dana Heller., and Stimpson, have been among the mos't prominent systematic writers on the Crustacea; and of floe naturalists of the present day, 31. A. Milne-Edwards of Paris, Mr. 3liers of the British 31useum, M. de Man of Leyden, and Prof. Wood-Mason of Calentta, have paid especial attention to the Crustacea of the Indian and Malayasian regions.