44 REPTILES. 



East Indies. Another with four toes, Lac. tetradactyla, Lacep. 

 Ann. du Mus. II, lix, 2*. In others the tympanum is concealed, 

 leading directly to Chirotes, and thence to the Amphisbsenjfi. There 

 is one species with five toesf; and a second in Brazil with four an- 

 terior and five posterior, the Hetrodactylus imbricatus, Spix, xxvii, 1 ; 

 a third with four to each foot J; a fifth, whose toes, to the number of 

 five before and three behind, are reduced to such small tubercles, 

 that it has at one time been considered as having three, and at ano- 

 ther but one§. From Guiana. 



Chirotes, Cuv. 



The Bimana resemble the Chalcides in their verticillate scales, and still 

 more so the Amphisbamas in the obtuse form of their head ; but are dis- 

 tinguished from the first by the absence of hind feet, and from the second 

 by the presence of the anterior feet. One species only is known. 



Chamcesaura pro-pus, Schn. ; Lac. lumbrico'ides, Shaw; Bipede 

 cannele, Lacep. I, xli, has two short feet, each having four toes, 

 with a rudiment of a fifth, completely organized interiorly, attached 

 by scapulas, clavicles, and a small sternum; but the head, vertebras, 

 and in fact the whole remainder of the skeleton, resembling that of 

 the Amphisbasnae. It is from eight to ten inches long, and about 

 the thickness of the little finger; flesh coloured; the back invested 

 by about two hundred and twenty half rings; there are as many on 

 the belly, which meet alternately on the side. It is found in Mexico, 

 where it feeds on insects. Its slightly extensible tongue terminates 

 in two small horny points; eye very small; tympanum covered by 

 the skin, and invisible externally; two series of pores before the 

 anus. I found in them but one large lung, and a vestige of a smaller 

 one as in most, Serpents ||. 



* It is the genus Tetradactylus of Merr., or Saurophis of Fitzinger. 



f This species forms the genus Chalcides of Fitzinger. 



X The genus Brachypus, Fitz. 



§ In the first case it is the Chalcide, Lacep., pi. xxxii, the Chamcesaura cophias, 

 Schn., the genus Chalcis, Merr., and the genus Cophias, Fitz.; in the second it 

 is the Chalcide monodactyle, Daud., or the genus Colobus, Merr.; but all these 

 genera are reducible to one single species. 



|| The genera which terminate this order of Saurians interpose themselves in so 

 many various ways between the ordinary Saurians and the genera placed at the head 

 of the Ophidians, that several naturalists now think it improper to separate the two 

 orders; or they establish a single genus, comprising, on the one hand, the Saurians, 

 with the exception of the Crocodiles, — and the Ophidians of the Anguis family on 

 the other. But among the fossils of the antient calcareous formations, we find two 

 much more extraordinary genera, which, to the head and trunk of a Saurian, add feet 

 attached to short limbs, and formed of a multitude of little articulations collected 

 into a species of oar or fin, similar to the fins or fore feet of the Cetacea. 



One of these genera, Icthyosaurus (a), had a thick head attached to a short 

 neck, enormous eyes, moderate tail, an elongated muzzle armed with conical teeth 

 fastened in a groove. Different species, some of them very large, have been dis- 

 interred in England, France, and Germany. 



The other, Plesiosaurus («), had a small head attached to a long serpentlike 



IgSg^ (a) Mr. Mantcll informs us, that vertebra?, teeth, and other bones of the 

 Plesiosaurus have been found in the strata of Tilgate Forest. To M.r. Conybeare 



