BEETLE 475 ander W. Thayer, an American, who has de- voted many years of his life to the minute researches necessary to make an exhaustive biography of the composer. The work at the present date (1873) is unfinished, only one volume having been published, and that in German. The other principal sources of in- formation upon this subject are as follows: Wegeler and Ries, Biograph-ische Notizen uber L. v. Beethoven (Coblentz, 1838) ; Dr. A. B. Marx, Ludwig van Beethoven's Leben und Schaffen (2 vols., Berlin, 1859 ; 2d ed., 1863) ; L. Nohl, Beethoven's Leben. (2 vols., Vienna, 1864-'7); and Ludwig van Beethoven's Bio- graphie und Characteristic, by Dr. Heinrich Doring, prefixed to the Wolfenbuttel edition of the composer's pianoforte sonatas. BEETLE, a very numerous and well known order of insects,' constituting the coieoptera. They have usually 4 wings : 2 membranous, the organs of flight, filmy and folded trans- versely ; and 2, anterior and superior to these, of a harder consistence, protecting the former, and called elytra. They all have mandibles and jaws. The head varies greatly both in size and form in the ditferent tribes; it pre- sents 2 antennae, of various forms, of which the joints are generally 11 in number; the eyes are .2, and compound ; they have no simple eyes, according to Latreille. The mouth con- sists of a labrum ; 2 mandibles, usually of a horny consistence ; 2 jaws, each one having 1 or 2 palpi ; and a labium of 2 pieces, accom- panied by 2 palpi. The anterior segment of 1. Digestive apparatus. 2. Mouth. . Thorax. 4. Fore leg. 6. Hind leg. 6. Nervous system. the thorax, or the corslet, which is in front of the wings, is larger than the other two seg- ments, and is free in its movements ; it sup- ports only the first pair of legs ; the other seg- ments are united together, and nearly im- movable ; the mesothorax supports the second I pair of legs and the elytra ; the membranous wings and the third pair of legs are attached j to the third and last segment. The elytra and | wings originate from the lateral and upper portions of the segments. The former are of a firm consistence, almost crustaceous, and, in a state of rest, are applied horizontally one against the other along their internal edge ; they almost always conceal the true wings, and are generally as long as the body ; in the act of flight they are usually extended, though in some species destitute of true wings they are united on the dorsal suture; in the wingless genera the elytra are always found. The ab- domen is sessile, or united to the chest by its greatest breadth, composed of 6 or 7 rings, membranous above, where it is protected by the elytra, and of a more horny consistence below. In the males the anterior pair of legs are often stronger, and the tarsi broader, than in the females. All the coieoptera masticate, and are accordingly provided with instruments proper for cutting and triturating their food ; the salivary glands are quite rudimentary, and few in number; the digestive canal varies in length according to the habit of life, but it gen- j erally is much longer than the body. The sexes I are separate, and the act of reproduction is a [ true sexual connection. The organs of respira- j tion are stigmata along the sides of the body, I and tracheae pervading all parts of the system. ! The abdomen encloses a fatty tissue, apparently | connected with nutrition, which causes many 1 of these insects to be eagerly sought for as food by the savage tribes of the old world. They undergo a complete metamorphosis; and the larva? or grubs are generally soft-bodied, and provided with 6 legs; it is in this state that they are so destructive to vegetation. The males perish soon after the sexual union, and the females die shortly after the eggs have been deposited'. The coieoptera have been variously divided by different authors ; the divisions of Latreille, according to the number of the joints in the tarsi, have been generally adopted by naturalists. These divisions are the following: 1, pentamera, having 5 joints on each foot; 2, heteromera, having 5 joints to the anterior 2 pairs of feet, and 4 joints to the posterior pair ; 3, tetramera, having 4 joints to all the feet ; 4, trimera, having no more than 3 joints to the feet. Though this system is artificial, and in many points very defective, it is still sufficient to give a clear idea of this very complex order. Latreille makes 20 families. The pentamera include: 1. The carnivora, whose varied spe- cies all agree in being exceedingly voracious ; they are both terrestrial and aquatic ; the for- mer have been divided into the tribes cicin- deletce and earabici ; the latter constitute the tribe hydrocanthari. The eicindelce are very beautifully ornamented, of light and active forms, quick in their motions, darting on their insect prey, which they devour alive; they prefer light and sandy districts exposed to the sun ; they are extensively distributed over the
Page:The American Cyclopædia (1879) Volume II.djvu/495
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