Klein, Jacob Theodor

(b. Königsberg, East Prussia, 15 August 1685; d. Danzig [now Gdansk, Poland], 27 February 1759)

zoology.

Klein’s Naturalis dispositio Echinodermatum (1734) was one of the earliest monographic treatments of the sea urchins. It includes descriptions, illustrations, and a classification of both recent and fossil sea urchins. Klein called these the Echinodermata and divided them into three classes according to the position of the vent. The classes were then divided into nine sections, corresponding to the genera of later authors, and twenty-two species. Although altered and enlarged, this work was a major source of information on the Echinoidea for zoologists and paleontologists throughout the eighteenth century and remained a point of departure in discussions by such early nineteenth-century authors as James Parkinson.

Klein, who studied law at the University of Königsberg and served as court secretary in Danzig from 1714, had many and diverse interests in natural history besides sea urchins. He developed a botanical garden in Danzig, founded and directed a naturalist’s society there, made extensive collections, and published about two dozen monographs, including studies of birds, fishes, reptiles, and invertebrates other than the sea urchins, particularly the mollusks. Fossils are dealt with in various publications, and Klein edited the Sciagraphia lithologica curiosa, seu lapidum nomenclator (1740) of J. J. Scheuchzer, which was published after Scheuchzer’s death.

A principal concern in his monographs is classification. Klein’s taxonomic method was based entirely on external characteristics, such as the number and position of limbs and the mouth; and he vigorously opposed any method, including the Linnaean system, based on characters not visible externally.

Klein was a member of the St. Petersburg Academy of Sciences and the Royal Society of London. He was a frequent contributor to the latter’s Philosophical Transactions between 1730 and 1748.

BIBLIOGRAPHY

I. Origional Works. Klein’s writings include Naturalis dispositio Echinodermatum. Accessit lucubratiuncula de aculeis echinorum marinorum, cum spicilegio de belemnitis (Danzig, 1734), trans. into French as Ordre natural des oursins de mer et fossiles; avec des observations sur les figures des oursins de mer, et quelques remarques sur les bélemnites (Paris, 1754), Latin ed. rev. by N. G. Leske (Leipzig, 1778); and Summa dubiorum circa classes quadrupedum et amphibiorum in celebris domini Caroli Linnaei systemate naturae, sive naturalis quadrupe dum historiae promovendae prodromus, cum praeludio de crustatis (Leipzig, 1743), which summarizes Klein’s feelings about a taxonomic method. A list of Klein’s works is in Johann Georg Meusel, Lexikon der vom Jahr 1750 bis 1800 verstorbenen teutschen Schriftsteller, VII (Leipzig, 1808), pp. 53-60.

II. Secondary Literature. The brief biographical sketch in Allgemeine deutsche Biographie, XVI (repr. Berlin, 1969), pp. 92-94, is based on Christof Sendel, Labrede auf Herrn Jacob Klein (Danzig, 1759).

Patsy A. Gerstner