REPTILES. 



tional length lliaii in birds. In confequcnceofthis length of the 

 canal it is plaited on the produftion of the peritoneum in the 

 chelonian, faurian, and ophidian orders, or extremely fmuous 

 and folded on itfelf in tiie batracians. When tiie curva- 

 tures are deitroycd, and the duft is llretched in a ftraight 

 line, it is four times the length of the animal in the fala- 

 mander. Its parieles confill at firfl of a thin membrane, 

 they become afterwards thicker, and aflume the appearance 

 of a glandular llrufture. The ovidudls end in the frogs by 

 a dilatation, whicli opens into the cloaca. 



The thick, flefliy part of the oviduft in the tortoifcs has 

 been frequently called the uterus : the two ovidufts open 

 feparatcly. Caldefi offervaz. intorno alle Tartarughe, tab. 6, 

 fig. 9, lo. 



An uterus is alfo fpoken of by fome in the frogs, al- 

 though the generation of thefe animals has nothing in it 

 like utero-cellation, and the ova are fimply tranfmitted 

 through the tubes, without being retained i.i them to 

 undergo any part of their developcment. " The frogs of 

 this country," fays Blumenbach, " have a large uterus 

 divided by an internal partition into two cavities, from 

 which two long convoluted ovidufts arifc, and terminate 

 by open orifices at the fides of the heart. As the ovaria lie 

 under the liver, it is difficult to underftand how the ova 

 get into the above-mentioned openings. The uterus opens 

 into the cloaca." (Comparative Anatomy, tranflated by 

 LawTence, p. 446. ) " The toads have not the large uterus, 

 but their ovidudls terminate by a common tube in the 

 cloaca." (Ibid.) For dehneations of thefe parts in the 

 frog and toad, fee Roefel, tab. 6, 7, 8, and 21. The rana 

 pipa (Surinam toad) has the fame ftrufture. See Camper 

 in the 9th vol. of Commentat. Soc. Reg. Scient. Gotting. 

 p. 129. Alfo in his Kleinere Schriften, v. i. pt. i. tab. 3. 

 fig. I. 



Female Organs of Copuhiion. —The male penis in copu- 

 lation palles into the female cloaca. Does it go into the 

 ovidufts ? 



The chelonian reptiles have a clitoris very analogous to 

 the penis of the male, from which it differs only in its 

 fmaller fize. It is long, grooved lengthwife, and termi- 

 nated by a rounded glans. Retraftor mufclcs, analogous to 

 thofe of the penis, draw back the chtoris into the cloaca, 

 when it has been extended. 



No clitoris has been difcovered in the other reptiles. 



Dorfal Cells of the Rana Pipa (Surinam toad, bufo dor- 



fi<rer). It is fingular enough to meet with in a toad a 



ilruiSture analogous to that of the abdominal pouch of the 

 marfupial mammalia. The (liin of the bulk is excavated in 

 the female pipa by a large number of cells, (of which, 

 Cuvier fays, eighty have been counted, ) in which the ova 

 are placed, and changed into tadpoles, and the latter grow 

 and are raetamorphofed. As far as ^n examination of in- 

 dividual, preierved for a long time in fpirits of wine, will 

 enable us to judge, tlie parietes of thefe cells do not feem 

 to have any thing in their organization diftindi from the 

 reft of the Ikin. 



Naturaliils fuppofed at firft, that the ova grew on tlie 

 back of the female, and that the male fecundated them in 

 that fituation : but obfervation of the living animal, and 

 anatomical inveftigations, liave (hewn the incorreclnefs of 

 this notion ; have proved, that the generative organs re- 

 femble thofe of other female toads ; that the pipa lays her 

 ova like the other toads ; and that the male fattened on her, 

 as in the ordinary mode belonging to this order, covers her 

 with the eggs after they have been fecundated. The eggs 

 are then enveloped in a fluid, which caufes the flcin of the 

 back to fwell round them : thus tiiey are contained in 



rounded cavities. The tadpoles are produced there, viw 

 their membranous tails, and are developed in this fituatio:i. 

 which they do not quit until they have reached their perfect 

 ilate. The female then caufes the cells to difappear froni 

 her back, by rubbing it againll hard fubllances. Befide- 

 the works of Camper already referred to, concerning tht- 

 anatomy of this extraordinary creature, fee Blumenbach's 

 Abbildungen, W 36, for excellent figures of the animal, 

 and of its young in three ftates : i ft, as a long-tailed tad- 

 pole, with Imall procefles of hind legs, and no trace of fore 

 limbs ; 2dly, as a four-fi.iotcd creature, with the tail reduced 

 to an infignificant fize ; and 3dly, with the tail entirely re- 

 moved. The fkeleton is figured by Schneider, in his 

 Hift. Ampliib. Fafcic. I. 



Phjfiology of the Generative Organs. — In the whole clalt 

 it is quite obvious, that the germ or rudiment of the new 

 being is produced by the female in the ovarium, a point 

 which does not admit of direct proof in the mammalia. 

 This " pre-exiftence of the germ" to the aft of copulation, 

 and its formation in a peculiar organ of the female, de- 

 monftrated fo clearly in reptiles, illuilrate one of the moft 

 curious points in the theory of the natural reproduttion 

 of organized beings, or generatiorij^ and overturn many of 

 the fpeculations on that fubjeft. Thefe germs acquire 

 confiderable fize in the ovaries, and are therefore diitindlly 

 vifible before the approach of the male. They pafs from 

 the pares juft mentioned into the ovidutls, and thence out 

 of the body through the cloaca, having received in their 

 paflage through the dudls fome external coverings. An 

 apphcation of the fecundating liquor fecreted by the male 

 is neceliary to the evolution ot thele germs ; they may be 

 ejected from the body without the embraces of the male, 

 as in the frog, toad, or newt, if they arc forcibly feparated 

 from the male after copulation has begun, but then they 

 are not evolved- 



Swammerdam and Rocfcl were of opinion, that the eggs 

 were loofe in the abdominal cavity, and taken up thence by 

 the oviduct. Spallanzani found them in the abdomen only 

 thrice in moi-e than two thoufand diffeftions ; and hence fup- 

 pofes that the circumllance muft have been a deviation from 

 the accuilomed courle in thefe inrtances. 



Although the motions and vital functions of reptiles 

 feem very languid in comparifon to thofe of the warm- 

 blooded clafles, they exhibit confiderable ardour and mani- 

 feftations of lively feeling in their amours. " As foon," 

 fays Spallanzani, " as the eggs begin to be difcharged, the 

 agitation of the female is extreme ; ftie darts backwards 

 and forwards, rifes towards the furface of the (vater, and 

 then finks, keeping the hind legs conltantly itretched out, 

 and croaking in a low voice. The male, keeping his hind 

 legs clofe to his body, throws himfelf into ftrange con- 

 tortions, and accompanies the croaking of the female with 

 a kind of interrupted noife, v.nich I cannot exprefs by 

 words." Diflertatious, v. 2. § II. 



In the work juft quoted, which contains the moft original 

 and interefting collection of facts concerning the whole 

 affair of ger.eration, Spallanzani gives the following ac- 

 count of the amours of the water newt, which are the 

 more curious, inafmuch as there is not only no real copula- 

 tion by the introduction of a male member into the female 

 organs, but not even any conjunction of the bodies, as in 

 frogs and toads. " The niciL purfues the female, which at 

 firft makes a (how of flying, but then ftops of her own 

 accord. He then approaches her in fuch a manner, that 

 the lower part of his head comes in contact with the upper 

 part of the head of the female ; and this is done while the 

 animals are in fuch a pofture, that their bodies form an 



anjrle, 



