Centipedes and Millipedes.
These are creatures with long, worm-like bodies, composed of a number of rings or segments, each provided with one or two pairs of legs. They have one pair of antennæ, like insects, but they pass through no metamorphoses, nor do they moult. Instead of this, they begin their existence, on quitting the egg, without legs, or with only three pairs of legs, and continue to add to the number of their segments and legs until they have attained their full growth. They are called Centipedes, or Hundred-legs, and Millipedes, or Thousand-legs; but in the majority of species the number of legs is considerably below 100, though in some few it may exceed 300.
The Centipedes have only one pair of legs attached to each segment of the body, and are carnivorous, being armed with a pair of strong mandibles, which are perforated poison-fangs. The British species are all small and harmless, but the bite of the large tropical centipedes is more painful and almost as dangerous as that of a snake. Centipedes are long, broad, flattened creatures, with about twenty-one pairs of legs, and sometimes measure more than a foot in length. A reddish centipede, belonging to an allied family, is common in England under stones and in loose mould. It has long antennæ and fifteen pairs of legs, and feeds chiefly on worms. It is about an inch long.
Photo by W. P. Dando, F.Z.S.] [Regent's Park.
GIANT CENTIPEDE.
Most centipedes have considerably fewer than a hundred legs.
The Electric Centipedes are much longer and more slender than the others in proportion to their length, with rather short antennæ, and short and very numerous legs. They are of a white or yellow colour, and 2 or 3 inches long. All are nocturnal in their habits, and feed on decaying animal or vegetable matter, and are fond of ripe fruit. They emit a pale phosphorescence, visible in the dark along the track over which they have crawled.
Millipedes are not venomous, and feed chiefly on soft vegetable matter. Except the first three behind the head, which are provided with only one pair each, every segment bears two pairs instead of one pair of legs. The Common Snake-millipede is about an inch and a half long, and is brown, with yellow rings and ninety-nine pairs of short white legs. It is nearly as destructive as the Wire-worms, which it resembles in its habits, and may often be seen clinging to a partly eaten potato. Millipedes are able to roll themselves up into a spiral. Many foreign kinds grow to a much larger size, measuring nearly a foot in length. They are more frequently sent to Europe from foreign countries than centipedes, probably because they are sluggish, harmless creatures which do not bite.
The members of one family of millipedes, called Pill-millipedes, are so similar to wood-lice in shape and appearance that they might easily be mistaken for them, and they exhibit the same habit of rolling themselves up into a ball. One species is not uncommon in England.