Photo by W. Saville-Kent F.Z.S.] [Milford-on-Sea.
FIGHTING CRABS.
The males are remarkable for having one large scarlet claw, the other being rudimentary (the females possess two small claws only). The eyes also are seated at the end of long stalks.
Some crabs are smooth and shining, but others are covered with bosses, excrescences, and spines, which give them a very formidable appearance, and must be a useful protection against any enemies to whose attacks they are exposed. In many species one of the two great claws is always much larger than the other. Some have round bodies, others are oval or nearly square; some have short legs, and others very long ones. The species differ much in their habits; and in tropical countries there are land-crabs which live entirely on shore, and others which are amphibious, and climb cocoanut-trees to get at the nuts. As a general rule, however, crabs are carnivorous and marine, and play the part of sea-scavengers.
The King-crabs differ very much from any now living in the British seas, but are generally considered to be allied to the Trilobites, an extinct family which appears to have been extremely numerous in very ancient seas. King-crabs are 2 or 3 feet long from the front of the body to the end of the tail. The front part of the body is entirely covered by a curved oval shield, while the hinder part of the body is much narrower, and armed at the sides with strong teeth directed backwards, and also with a long and strong spear, something like that of a sword-fish on a small scale, as long as the rest of the body. The few species known exhibit an instance of what is called "discontinuous distribution," since they are found only on the coasts of the Moluccas, East Indies, and the Southern United States and West Indies.
Scorpions, Spiders, and Mites.
These creatures form a peculiar group in which there are only two principal divisions of the body, the head and thorax being fused into one mass, and the abdomen forming a separate division. In the Mites, however, the body forms a single round or oval mass, even the division between the thorax and the abdomen having disappeared. The members of the group have no antennæ, but two pairs of jaws and a pair of palpi, frequently very long, and armed with a pincer-like arrangement at the end, in which case they are called "foot-jaws." Except in some of the mites, which have only four or six, all the group have eight legs. They pass through no metamorphosis, but moult several times after quitting the egg before attaining their full growth. They have frequently several pairs of simple eyes, but no compound eyes like the large pair on the head of most insects.
In the Scorpions, of which there is a considerable variety in different parts of the world, the united head and thorax are comparatively short; but the abdomen is very long, and divided into a broad half, consisting of seven segments, and a narrow tail of five very movable segments, besides a sharp, curved sting at the extremity. There are from three to six pairs of eyes on the head and thorax, and in front of the body projects a pair of very large pincer-bearing foot-jaws. Scorpions are generally of a yellowish or black colour; and the largest black scorpions of Africa and India sometimes measure as much as 9 inches in length. They are nocturnal creatures, hiding under stones, or in holes in the ground, or in crevices in walls during the day. They kill the insects and other small animals on which they feed with their stings, the sting of one of the large black scorpions, like that of the large tropical centipedes, being as painful and dangerous as that of a snake. There are a few small and comparatively harmless species found on the shores of the Mediterranean, but most of the scorpions inhabit warmer countries.
Photo by Highley.