n. (Zoöl.) An animal of the second sub-kingdom, which includes invertebrates, having the body and members jointed. See ANIMAL KINGDOM.
☞ There are five classes of articulates, belonging to two divisions, a land and a water division, as follows:—
Divisions. Classes.
A. The LAND DIVISION. Respiration by means of air-vessels called tracheæ, ramifying through the body, the openings to which are named spiracles.
1Sense 1. INSECTS. Body consisting of three parts, the head and thorax being separate segments, and distinct from the abdomen; legs six; usually two or four wings.
2Sense 2. SPIDERS. Body consisting of two parts, the head and thorax being united in one segment, and distinct from the abdomen; legs eight.
3Sense 3. MYRIAPODS. Thorax not distinct from the abdomen; feet many: form worm-like. Includes Centipeds.
B. The WATER DIVISION. Respiration by means of bronchia gills; or, in small species, the surface of the body, or of some part of it, acting as a bronchia.
4Sense 4. CRUSTACEA. Body consisting of two parts, the head and thorax being united in one segment and distinct from the abdomen; legs mostly ten or fourteen, sometimes more, rarely less. Includes Crabs, Lobsters, &c.
5Sense 5. WORMS. Thorax not distinct from the abdomen; feet wanting, their place sometimes supplied by bristled tubercles. Includes the Earth-worm, Leech, Annelids, Intestinal Worms.