TARDE, GABRIEL (1843-1004), French sociologist, was born at Sarlat (Dordogne) in 1843. Entering the legal profession, he was for some time a juge d'instruction in his native town, becoming afterwards head of the statistical department of the ministry of justice. He also held the professorship of modern philosophy at the College de France in Paris, and was elected a member of the Academic des sciences morales et politiques in 1900. Attracted to the study of criminology by the opportunities of his profession, he gradually built up for himself a reputation as an acute observer of the phenomena of the subject, while at the same time he made striking and original deductions of his own. Special reference may be made to his theory of " imitation " as outlined in Les Lois de limitation (1890), and further elaborated in Logique sociale (1895). He also wrote L'Opinion et la foide (1901); Les Transformations du droit (1894); Les Transformations du pouvoir (1899); L ' Opposition universette (1897) and Psychologic economique (1902; Eng. trans., Social Laws, 1899). He died in Paris in 1904.
See bibliography of. the sociological writings of Tarde in M. M Davis, Psychological Interpretations of Society (Columbia University Press, 1909); also A. Matagrin, La Psychologie sociale de Gabriel Tarde (Paris, 1910), apparently Arthropodous animals whose relationship to the great classes of this sub-kingdom is masked by degenerative modification. They are microscopical in size and live in damp moss or water. The body is elongated and furnished with four pairs of short, unjointed, stump-like legs, each terminated by a pair of claws. The legs of the posterior pair project from the hinder extremity of the body and the anus opens between them. The mouth, situated at the opposite end and armed with a pair of stylets, leads into an oesophagus, into which the ducts of a pair of so-called salivary glands open. Behind this point there is a muscular pharynx or gizzard, which communicates with the wide intestinal tract. No organs of circulation or respiration are known; but the nervous system is well developed, and consists of a pair of ganglia corresponding with the limbs and connected by longitudinal commissural chords. Anteriorly these chords embrace the oesophagus and unite with the cerebral mass which innervates the pair of eyes when present. The sexes are not distinct, the sexual organs being represented by a pair of testes and a single ovary, which open together into the posterior end of the alimentary canal. The Tardigrada have been regarded as degenerate Acari largely on account of their possessing four pairs of ambulatory limbs, which is considered Milnesium tardigra, Schrank. a, ovary; can al ; e...e, legs.
to be an Arachnidan characteristic. But they cannot be affiliated with this order on account of the total suppression of the abdomen, of their hermaphroditism and of the communication that exists between the generative organs and the alimentary tract. These last characteristics also separate them essentially from the Pycnogonida, some members of which resemble them to a certain extent in having only four pairs of limbs, no gnathites, no respiratory organs, a ganglionated ventral nervous system, and the abdomen reduced to a mere rudiment projecting between the last pair of legs.
Several genera and species of Tardigrada have been described, perhaps the best known being Macrobiotus schultzii and Milnesium lardigradum. (R. I. P.)
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)