Page:The American Cyclopædia (1879) Volume VII.djvu/668

 656 GECKO situated on the Laucli in a valley of the Vosges mountains, 15 m. S. W. of Colmar; pop. in 1871, 11,338. It has three gates, a fine promenade, two handsome churches, and many Swiss cha- lets and pleasant cottages on the slopes of Mount Gebweiler, the culminating point of the Vosges (4,700 ft.). There are manufactories of cloth, cotton goods, ribbons, chemical pro- ducts, machinery, and other articles. Previous to the Franco-German war it belonged to the French department of Haut-Rhin. -GECKO, a name applied to a family of noc- turnal lizards (ascalabotm of Dumeril and Bi- bron), numerous in species, living in warm cli- mates, and presenting characters of form, struc- ture, and habits which make the group as dis- tinct as that of the crocodiles or chameleons. Their size is small ; the head wide, flattened, covered with scales, with marginal scuta at each jaw ; the neck short ; the body depressed, stout, thickest in the middle, without crest on the back, generally covered with small imbri- cated scales and scattered tubercles, smallest on the back ; the tail moderate ; the feet five- toed, the thumb often very short, and the other fingers equal, flattened below and lobed at the end; the tongue is fleshy, short, slightly pro- tractile, free and scarcely emarginate at the tip ; the eyes very large, covered as in serpents by a transparent immovable lid, behind which these organs have free motion ; the pupil ver- tical, and often linear as in nocturnal animals generally ; the opening of the ear is distinct, and the tympanum depressed ; there are no teeth on the palate, those of the jaws thin, entire, numerous, with cutting edges, and adhering to the internal margin ; femoral pores occasionally present, but usually absent ; besides the leaf- like expansion at the end of the toes, nails are generally present, capable of retraction, as in the cats, the latter favoring their progression in climbing on smooth surfaces. The tail is shorter than in ordinary lizards, and the flat- ness and width of the head give them some- what the aspect of salamanders ; the mouth is deeply cleft, and the" widely expanded jaws may be kept open for a long time, the cavity of the mouth being shut off* from the throat by the application of the base of the tongue to the posterior part of the palate ; from the shortness of the robust legs, the abdomen touches the ground in walking. This reptile is mentioned by Aristotle, and the modern name gecko is derived from the sound made by some of the Indian species, resembling the click of the hostler urging on his horses, and was first given by Laurenti ; this genus was the ascala- botes of Aristotle, the stellio of Pliny, and the tarentola of the ancient Italians. Their colors are generally gray or yellowish, but some have brighter tints which can be varied like those of the chameleon, probably by the same changes in the reflecting surface of the integuments; the sides of the body, limbs, and tail are some- times fringed with membranes. In many spe- cies there is a line of pores along and under the thighs, from which a fatty moisture distils ; some species of a genus will have these, and others not, and sometimes one sex only will be destitute of them. The tail, as in salamanders, is ruptured with facility, and is reproduced readily, often in a deformed manner. Their food consists of larvaa and insects, which they pursue into their leafy retreats; the imbricated plates on the bottom of their feet, like those of the tree frog and flies, enable them to climb smooth walls and similar surfaces, and to ad- here to them with the back downward ; by means of their sharp, curved, retractile claws, they can ascend trees and rough objects with ease and rapidity ; from the quickness of their movements, their suddenly becoming motion- less, and remaining so for a long time, and their resemblance to the colors of the substances on which they are placed, they are difficult to ob- tain, and not easy even to see ; they hunt for food both by night and day ; the same qualities which fit them for the pursuit of living prey enable them to escape their bird enemies. These reptiles are objects of horror and repug- nance, from the erroneous idea that they exude a poison so powerful and subtle that their touch, a drop of their saliva, or a scratch with their nails, will produce leprosy and other cu- taneous diseases, often ending fatally. They like to approach human habitations, as there they find in greatest abundance their insect food ; their ill-shaped body, smooth or spiny, dull colors, large head, their enormous staring eyes, rapid and silent motions, and familiarity in houses, render them very disagreeable, but by no means dangerous inmates. Found in all warm climates, they are very uncommon in Europe (two or three species), and most abun- dant in Asia, America, and Africa, and the Pacific islands are well supplied with them. They have been divided into genera according to the form and structure of their toes; but these generic characters in a family so nearly alike in its members are very unsatisfactory, and great and unnecessary multiplication of genera has been the result of the labors of various systematists. The arrangement of Du- m6ril and Bibron, which differs but little from that proposed by Cuvier in 1829, is as fol- lows : 1. Platydactylus (Dum. and Bibr.), with toes enlarged for their whole length, with finely plicated strias beneath ; of those species having the feet cloven, some have all the toes unarmed, others all unguiculate, oth- ers with the thumb only or with the second and third fingers unarmed ; of those with pal- mated feet the fingers are either all unguicu- lated, or the thumb alone is unarmed ; there are about 20 species, of which the varieties have been made into genera by Fitzinger, Wieg- mann, Kuhl, and others. 2. Hemidactylus (Cuv.), with the toes widened only at the base into an oval disk striated beneath; about 15 species. 3. Ptyodactylus (Cuv.), with the toes enlarged at the extremity into a cleft oval disk, striated below like a fan, and all armed with