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 GMELIN GNAT tened shield, is about 3 ft. ; the size of the glyptodon may be imagined from the measure- ment of its carapace in the museum of the royal college of surgeons: the length, following the curve of the back, is 5 ft. 7 in. in a straight line, or the chord of the arc, 4f ft. ; the breadth, following the curve, is 7 ft. in a straight line, 3 ft. The tail measured H ft- in length, and 14 in. in circumference at the circular base; it was slightly depressed toward the apex, and gently curved, with the concavity upward ; the caudal vertebrae were enclosed in an inflexible sheath of bony plates, terminated by two ossicles, like a bivalve shell, enabling it to pierce the soil if necessary. The feet were short and stout, armed with depressed nails. The glyptodon, in its firm, convex car- apace, scale-covered tail and head, short limbs, and consequent slow motions, presents many external analogies to chelonian reptiles, and in its size and shape must have resembled rather the living Galapagos tortoise than the great armadillo. Like the living armadillo, the ex- tinct glyptodon was confined to the warm parts of South America. Other species described by Owen are G. ornatus, G. reticulatus, and G. tuberculatus, all obtained from the vicinity of Buenos Ayres. GMELIJf. I. Joliann Georg, a German natural- ist, born in Tubingen, June 12, 1709, died there, May 20, 1755. In 1731 he became professor of chemistry and natural history in St. Peters- burg. In 1733-'43 he made a scientific journey through Siberia. In 1747 he returned to Tu- bingen, and in 1749 was appointed professor of botany and chemistry there. His Reisen durch Sibirien (4 vols., Gottingen, l751-'2) and Flora Sibirica (4 vols., St. Petersburg, 1749-70) are his principal works. II. Samuel Gottlieb, a Ger- man botanist, nephew of the preceding, born in Tubingen about 1744, died at Akhmetkent, in the Caucasus, July 27, 1774. He was profes- sor of botany in St. Petersburg, and travelled extensively through southern Russia and the adjacent countries. While on his way from Derbend to Kisliar, he was seized and im- prisoned by the khan of the Kaitak tribe, and died of privation and ill treatment. His chief works are Historia Fucorum (1768), and Reisen durch Russland zur Untersuchung der drei Naturreiche (4 vols., l770-'84), of which the concluding part is by Pallas. III. Joliann Friedricb, nephew of Johann Georg, born in Tubingen, Aug. 8, 1748, died in Gottingen, Nov. 1, 1804. In 1771 he became professor of natural history and botany at Tubingen, and in 1778 professor of medicine and chem- istry at Gottingen. He published, among other works, Onomatologia Botanica completa (10 vols., 177l-'8) ; Allgemeine Geschichte der mineralischen Gifte (1777); Allgemeine Ge- schichte der Pflanzengifte (1777) ; and Ge- schichte der Chemie (3 vols., !797-'9). He was also the editor of the 13th edition of Linnseus's Systema Natures. IV. Leopold, a German chem- ist, son of the preceding, born in Gottingen, Aug. 2, 1788, died in Heidelberg, April 13, 1853. He was educated at Gottingen, Tubin- gen, and Vienna, and from 1817 to 1851 was professor of medicine and chemistry at Heidel- berg. In 1820 he made with Tiedemann a series of experiments on digestion, the result of which was published in his Die Verdauung (2 vols., 1826-'7). His principal work is his Handbuch der theoretischen Chemie (3 vols., 1817-'19; 5th ed., completed by Schloss- berger, List, and Liebig, 7 vols., 1853-'62). There is an English translation of this work, by Henry Watt (9 vols., London, 1848-'55). GMUND, or Schwabish-Gmiind, a town of Wur- temberg, in the circle of the Jaxt, on the Rems, 28 m. E. K E. of Stuttgart ; pop. in 1871, 10,- 739. It has a Latin school, a Catholic normal school, institutions for the blind and the deaf and dumb, an insane asylum, two hospitals, important manufactures of gold, silver, copper, and bronze ware, and considerable hop culture. GNAT, a name commonly given to the fam- ily culicidce, of the proboscidean division of the order diptera or two-winged insects ; the cousin of the French, the mosquito of the 1. Female (greatly magnified). 2. Male. United States. The gnats belong to the genus culex (Linn.), which is characterized by a soft, elongated body ; long legs ; large head and eyes; long, many-jointed antennae, most plu- mose in the males; uniform and hairy palpi, longest in the males; a sucking proboscis, formed of a membranous sheath enclosing from two to six sharp bristles or lancets, which take the place of jaws, and whose punctures, therefore, are properly called bites ; the side pieces of this apparatus serve not only as suc- tion tubes, but as supporters and protectors of the lancets ; wings horizontal, delicate, and many-veined ; the winglets, two little scales behind the wings, and moving with them, are small ; behind these are the knobbed balancers or poisers. The old genus culex was divided by Meigen into three, and was by him re- stricted to such gnats as have the palpi in the males longer than the proboscis, and very short in the females; the other two were ano- pheles (Meigen), in which the palpi of the males are as long as the proboscis, and cedes (Hoff- mannsegg), in which they are very short in both sexes; to these were afterward added sdbeihes, with palpi shorter than proboscis; megarhinus, with very long recurved proboscis and short palpi; and psorophora, with a small