HERPETOLOGY. 



13 



v _ 



k. --. 



ever, that, under the ordinary temperature of the at- 

 ubl Pkyuo- mo pherc, the heat of these animal* u generally a few 

 degree* above that of the surrounding medium ; and 

 while lite cw^ir'"**, tliey have the power of pre< 

 a moderate temperature, and of resisting, to a cer- 

 tain degree, considerably inferior indeed to roan and 

 quadruped*, the extreme* of either heat or cold. See 

 Chap. IV. 



Almost all reptile* utter sound* more or less loud ; 

 the salamander and the green liaard being almost the 

 only known exception*; and it U even not certain 

 whether the former should be entirely excluded. Tur- 

 tle* and tnrtoisei hi** or sipb ; crocodile* low or roar, 

 iu H> loud a tone a* to resemble dutaat 

 r, while the young of th* anianU are said to 

 a noise like a cat, (but whether mtmiag or Bar- 

 ring we art not laid), and to utter piercing crie* if at- 

 tacked, when firat extruded from the egg. Iguana* 

 make a sort of whittling sound a* they nut along the 

 tree*, and the croaking of frog* and toad* U mffioiont 

 ly known. 



The organ* of voice in the*e animal* are very unple, 

 of a tingle larynx, without rtHtlottu, but in. 

 chord* of the glotiii. moved by 

 In tume apecic* of frog*. 

 there are astn nuranranou* 

 with the glottis, or pouches in the 



serve to in cram or modify the 





Of 



>!.!, 



TUB most ianportant of the 

 we are to notice in reptiles, an the i 

 pleen, and urinary organ*. 



The liver of these animal* i* always large, and in 

 some instances, a* in the salamaajder, its proportional 

 tagnifurlr is very rnajairsrvsbli , In the rhafcnisn* it 

 .dad into two rounded irregular lobes, the one 

 the right hvpochondrium, and the other 

 to the stomach at iu sasall csua>uiu It is 

 into two labs* m the crocodile and the 



lobe, differing in siat and figure iu the several tribe*. 

 In all the rkfnriaa* except the *" ~f, the liver 



nan ;, 



e a gall bladder, which ie more in- 

 with the liver, but i* proportionally 

 ad bird*. In the Chakv 



it wahw* wholly concealed in the right lobe of 

 the liver, and M found in a similar situation in croco. 

 There are generaily two dncta leading to the 

 ; one from the lirer, the hepatic duct, and the 

 other, tbe cystic, from the gall-bladder, and these, in 

 mmt m-Mnrr., run -vpir.'. !< ',..(! .-r. 



The position and siae of the pancreas are very va- 

 none, la moat of the Chelonians it M triangular, amftg*> 

 neraUy entire. In the crocodile it i* divided into lobe*. 

 la some of the B-traoaas, as the frag, it is lodged in 

 the arch of the steal rh toward* the sternal part of the 

 body ; in others, as the salamander, it is situated in the 

 last curve of the iwUatisM*. Tbe pancreatic duct i* 

 ingle, but in some instance*, as in the Ni- 

 it i. doable. 



in all reptile* ; bat its structoJ\ 

 m these animals, has been very im- 

 In the thtlonian, it 



like the kidney ; in the Saurians, it is elongated ; in Anatomy 

 most of the Batracians, as frogs and toads, it is small 

 and spherical, and in the former tribe ie situated in the 

 mesentery ; while in salamanders it is of au oblong 

 form. 



All reptiles appear to have kidneys ; but the .struc- Kidneys. 

 hire of these organs is extremely simple and uniform, 

 a* they have no distinction of cortical and inrduKiiry 

 substance, and no parts corresponding to the in/'un-ti- 

 hula and peivii in mammalia. In figure and situation, 

 however, they vary in the several orders. In the Che- 

 Ionian* they are short and thick, and lie far hack in 

 the cavity of the abdomen. In the Saurians they are 

 of an oval form, more or less flattened and elongated, 

 and in general they lie far back under the sacrum or 

 near the tail. It is uncertain whether their form varies 

 with age in all these animal* ; but it appears that in 

 young crocodile* they are entire, while in full thrown. 

 individual* of the same tribe, they are divided into se- 

 veral lobe*. In the Batracians, they are situated pretty 

 far forward* and very near each other, and resemble 

 those of the Saurians in form. 



All the reptile tribes have not a urinary bladder. It L'rinary 

 is found in the Chelonians, in whom it is very large, **/ 

 and i* more or less divided into two portions. Of 

 the Saurian*, only the tupinambis, iguanas, stellios, 

 chameleons, and dragons, have an urinary bladder. 

 It is found in the Ra' racians, in some of whom it con. 

 sist* of two membranous bags, while in others it is 

 single. 



In reptile* there is a common receptacle or passage cloaca, 

 for the urine and facet*, called clnaca ; and in those 

 tribe* that have no urinary bladder, the ureters, or 

 pipe* from the kidneys, open immediately into this re- 



of a peculiar nature take place in 

 Tim*, in the crocodile, there is a gland si- creuoni. 

 ea each aide of the lower jaw, just beneath the 

 -km, having a duct opening externally, and secreting 

 a substance that amella like musk ; while gland* of a 

 ajisilar nature are found in the cayman, near the anus. 

 In several of these animala, a* in toad* and salamanders, 

 an acrid fluid exudes through numerous porn of the 

 kin when they are irritated. Thi* fluid u not, how- 

 cvrr. poianaMii*. as has been supposed ; but, among 

 the Saurian*, the gecko* secrete from between their 

 toe* a matter which i* really of a venomous nature. 

 See GECKO in the subsequent Part. 



CHAP. VII. 

 Of Inttgttmalion in Reptilet. 



A coKDC*ABLK variety U found among the rep- 

 tile* with respect to their integuments ; and as these 

 varieties constitute many of the generic and specific 

 character*, it is necessary to examine them with some 

 minuteness. 



In all these animals there is the usual distinction of Cuticle. 

 eankli, true skin, and reie sxcewm. The structure of 

 tbe skin and rrto m*conux differs but little from that 

 of other animals, except hi the frog and toad, where 

 there i* this peculiarity, that the skin adhere* to the 

 part* beneath only at a few point*, so that it forms a 

 sort of loose bag about the animal, susceptible of occa- 

 sional inflation. The cuticle is extremely various in the 

 diflerent order* and tribes. In the CheJonians, though . 

 only the head, tail, and extremities, appear to be co* 



