Page:The American Cyclopædia (1879) Volume VI.djvu/247

 DKAGONETTI wide and flat at the base, round at the end, with rhomboidal imbricated scales, strongly ridged beneath. Among the species with a visible tympanum, and the nasal openings di- rected laterally, are : 1. The fringed dragon (D. fimbriatus, Kuhl), with the thighs fringed behind with triangular scales, and with longi- tudinal white lines on the wings ; the general color above is an olive gray with shades of brown in transverse bands, and whitish be- low ; this is the largest species described by Dume'ril and Bibron, the total length being about 11 in., of which the body is only 3 ; it is peculiar to Java. 2. The flying dragon (D. Daudinii, Dum.), from Java, grayish above with black spots, and the wings marbled with the same; total length about 9 in. Several other species are described from the East In- dies. There are two species which have the tympanum concealed under the skin, consti- tuting the genus dracunculus of Wiegmann; these are the lined dragon (D. lineatus, Dau- din) of Amboyna and Celebes, about 6 in. long, with the -back ash-colored, and the wings grayish brown with longitudinal white lines; and the Philippine dragon (D. spilopterus, Wiegm.), from the neighborhood of Manila, about 8 J- in. long, with red wings spotted with black or brown, and throat yellow with black dots. Dragons live almost entirely in trees and feed upon insects, which they catch with great dexterity. DRAGONETTI, Domenieo, an Italian contrabas- sist, born in Venice, April 7, 1763, died in Lon- don in 1846. His father was a player upon the double bass, and the young Dragonetti made such progress upon the instrument as to be re- garded as a prodigy at the age of 13. He was the first to make a solo instrument of the un- wieldy double bass. At the age of 24 he took up his residence in London, where he remained during the rest of his life as first double bass in the royal theatre and at the philharmonic concerts. He was esteemed the most accom- plished player upon his instrument of his time, and wrote for it many pieces in which were introduced passages that hitherto had been deemed practicable only for the violin. The instruments that he played were a superb Gas- paro da Salo and a Stradivarius. DRAGON FLY (libellula, Linn.), an insect of the family subulicornes of Latreille, or odonata (Fabr.), and the order neuroptera. The insects of this genus, called in this country " devil's darning needles," in the perfect form are light and graceful fliers, of the most brilliant and beautiful colors, with four large, shining, deli- cate wings of nearly equal size ; the mouth is provided with strong horny mandibles and spiny maxillae ; the eyes are lateral, large, and brilliant, with three stemmata on the top of the head ; the antennae consist of from three to six joints ; the legs are short, six in number, directed forward, arising from a firm thorax of three united segments ; the abdomen is very long, a flattened cylinder, soft, without sting 272 VOL. vi. 16 DRAGON FLY 239 or piercer, and in the males terminated by two lamellar appendages. In some genera the male sexual organs are placed in the second abdom- inal ring, and those of the female in the last ring ; the female deposits her eggs on aquatic plants beneath the surface of the water. From their lightness and beauty the French call them demoiselles. They are among the most vora- cious and cruel of insects, darting with swift- ness and ferocity upon gnats, mosquitoes, but- terflies, and almost any soft- bodied winged in- sect, eating even their own species. They are in no way injurious to man, but are directly beneficial in destroying many noxious insects. They hover over pools in search of prey, or dart from a post or fence upon insects coming near. They are equally carnivorous in the larva state, which they pass in the water. The larvae have six feet, and a very complicated ar- rangement of the parts forming the under lip, which covers the face like a mask, concealing the mouth; they crawl stealthily along the bottom, and spring their jointed mask upon in- sects and even small fishes with great precision. By a valvular apparatus at the end of the tail, they draw in and expel water, as a means of locomotion. They remain several months in the water, and change their skins several times. The nymphs have rudimentary wings, and when they are ready to assume their final change the brilliant eyes of the future fly may be seen through the envelope ; they crawl out of the water upon some bank or aquatic plant, where the pupa skin becomes dry and crisp and bursts open on the back. During the drying of the wings the insect bends the body into a cres- cent, that the delicate tissue may not be dis- turbed by contact with any foreign substance. The anterior nervures of the wings must be very strong, though light, to permit the rapid vibrations of these organs ; their section, as in the butterfly, presents the form found by engineers to be that of the beam of great- est strength and lightness, viz. : the greatest amount of material thrown into the oval Libellula trimaculata. flanges, connected by the thinnest possible median support. According to Drury, these insects are two years in reaching the* perfect form from the egg; after flying about a few