REPTILES. 



The falaniaiiders liavc fevcral glands ranged along the fenfes in this clafs, fays Daudin, if we may judge by the 



back, which form elevations or lumps on the iicin. Ilrudture of the nollrils. Reptiles do not fceni to employ 



The toads have them fcattcrcd irregularly on the whole their fmcU in difcovering or fclefting their food, or for any 



furface of the body ; we obferve, in particular, two which of the purpofes to which the faculty is fubfcrvient in other 



are very large, behind their ears ; thele glands produce an animals. 



acrid humour, which is a poifon to very fmall animals. We find, however, in the whole clafs, nafal cavities open- 



In lizards, we obferve a very regular row of fniall pores, ing on the fnout in front, and on the palate behind, lined 

 which alfo yield a vifcous humour. with a vafcular pituitary membrane, on which olfaftory and 



Abforption of ivater by the (Icin of the frog. — Townfon nafal nerves are diftributed. 

 found that the frog, and tree-frog, when placed on a moillened There are alfo different proj6fting laminx within the nofe • 

 paper, could abforb the moillure fo rapidly, as nearly to but they confilt or folds of the internal membrane, and are 

 double their weight in two hours, under certain circnm- not fuilained by offeous parts. The tortoife has three laminse, 

 ftances. He Hates that they do not drink, but take in all which divide the nafal cavity into feveral foifx. The middle 

 their fluid in this way. (See his Irafts and ubfervation:. in one correfponds to the external aperture of the noftrils ■ 

 natural hittory.) Daudin has verified the obfervation. He between it and the next there is an oblique canal, which 

 kept two frog» without any fluid lor feven days, and then leads to the poiterior nares. Wc lind only feme tubercles 

 placed them in a bottle on moillened flieets of paper. In in frogs, and other fmall fpecies. It does not appear that 

 two hours they had nearly doubled their weight. Hitt. any refearches have been made refpefting the parts in the 

 Nat. des Rejitiles, torn. i. p. 1 15. crocodiles. 



Fingers — The number of the fingers, and their flexibility, The olfaftory nerve differs in reptiles little from that of 

 vary nsore in reptiles than in all the otlier clafles. birds, as to its origin and courfe ; it differs lefs in its diltri- 



Common li/.ards have, in general, five fingers, of different bution, fince it alfo divides, according to Scarpa, upon the 

 lengths, well calculated to embrace objedts in every direftion. feptum, and the membranous fold correfponding to the 

 Some, as the crocodiles, have them palmated, at lealt in the fiiperior turbinated bone, without proceeding farther, 

 poiterior feet. Others, as the gecko, have them invefted The c.\-<fr«a/ jia/Tx of reptiles, more or lefs approximated, 



inferiorly with imbricated fcales. and fufceptible of contraction and dilatation, are ufually fur- 



The caineleon has them united by the (liin, as far as the nilhed with only fome flefliv ilrata, which dilate or contraft 

 nails, in two parts, which form the forceps. The (Icin of their their entrance. This is obfervable in the greater number of 

 inferior furface is furnilfied with fcnfible papill-je. The long lizards, which differ from each other only as to the pofition 

 lizards, called feps and chalcides, have only three very fmall of their external nares. They are clofclt to each other in 

 toes. The falamanders and frogs have them naked and def- the crocodiles. The tupinambis, the Hellions, and the ca- 

 titute of nails. In tree-frogs, the extremity of the toes is meleons, have them more removed, and fituated more later- 

 enlarged into a fpongy difk, capable of adhering with force ally. In the falamanders they are exceedingly fmall. In frogs 

 to bodies. In tortoifes, the toes are palmated. Laftly, we obferve a fmall tube, the motion of which is very ap- 

 the ferpents are completely deprived of feet and toes. parent, becaufe it is extremely ufeful in refpiration, as we 



The long feparate toes of the batracian order, and of have already fhewn. The tortoifes have alfo two very fmaU 

 feveral lizards, feem well enough calculated to ferve as or- approximated noftrils. In the matamata, and one or two 

 gans of touch ; they might be applied to objects, and would otiier fpecies, they are fituated at the end of a fliort carti- 

 furround them in various ways. They feem, however, to be laginous probofcis. The external nofe is alfo rather elon- 

 employed merely as inilruments of motion. gated in fome ferpents ; for example, in the vipera ammodytes, 



" It has been faid of ferpents (obferves Blumenbach), and the coluber nafica. In the reft of this order there are 

 with more ingenuity than truth, that their whole body is a fmall lateral nares, capable of flight extenfion. In the rattle- 

 hand ; by which they gain juft notions of the tangible pro- fnake, and fome others, there is a fmall blind hole, near the 

 perties of bodies. There is much more foundation for nofe, on each fide ; we have defcribed it under the head of 

 itating that the fenfe of touch, which is here meant, does pecuhar organs. See Scarpa de Auditu et Olfaft u, for a 

 not exill; in any of the amphibia." Syllem of Comparative defcription and figures of the nofe in the turtle and viper. 

 Anatomy, p. 319. The Organ of Tajle — All reptiles pollefs a tongue, but 



Among tiie reptiles the fcales vary greatly, according to whether they have the fenfe of talle is not fo clear. As ther 

 the genera. In tortc'fes they are plates ot a horny fub- all fvvallow their prey whole, there feems to be little room for 

 ftance, which are very hard and denfe in the greater number, the exercife of talte. We have already fpoken of the tongue. 

 But in the teltudo coriacea, and feveral others, they are foft in the account of the falivary glands ; and have entered fur- 

 and flexible : fometimes ihefe fcales are imbricated, as in the ther into a confideration of its mechanifm and moving powers 

 hawk's-bill turtle ; and then they are fmooth, or channelled in our defcription of the organs of maftication and deglu- , 

 longitudinally ; at other times they form compartments of tition. 



different figures: in the latter cafe they are more or lefs Subjlance of the Tongue. — Reptiles vary greatly with re- 

 convex, and furrounded with furrows, or concentric chan- fpetf to the tongue, as well as in many other circuraflances. 

 nels, in the midft of which are points, which are either The tongue of toads and frogs is entirely flefhy, attached to 

 fcabrous, elevated, or blunt, as in the fpecies named geo- the lower jaw, and, in a ftate of repofe, inflefted in the 

 metrica, gr^eca, &c. mouth. 



In the crocodile the fcales are bony, arranged in Iranf- In falamanders, it is attached as far as the point, which is 



verfe bands, and fituated, in refpecl to each other, like the not moveable, and the whole tongue is only free on its 

 ftones of a pavement. In the other lizards and ferpents lateral parts. Crocodiles have it attached to the lower jaw, 

 thoy confifl of horny fubftance, and prefent almoft every both by the edges and the point ; and authors long fuppofed 

 poiiible variety of form and arrangement. that this animal had no tongue. It is entirely flefhy in both 



Organ of Smelling. — This is lefs completely developed in the thefe genera, 

 amphibia than in the two warm-blooded claffes of vertebral The ftellions and the iguanas have a flefhy tongue, which 



animals. The fenfe of fmeUing is the moll imperfetl of the pofl'effes nearly the fame mobility as that of the mammalia. 

 Vol. XXIX. 5 F ' The , 



