REP 



the particulars may be ieen in the article Entomology, in 

 the divifion « of the larva Jlate," under the fubdivifion 

 «< hpiJopkra." 



The fecond, or extraordinary kind of reproduftive power, 

 is that by which wounds, fraftures, or any accidental 

 mutilation or lofs of parts of an organifed body, are re- 

 medied or reftored. Thisexills in very different degrees in 

 different departments of the animal kingdom. In man, and 

 fuch animals as are nearly allied to him, the property is very 

 limited, although fufSciently aftivc to be capable of re- 

 medying the effefts of great injuries. If a bone be broken, 

 a mufcle or tendon divided, or a piece of flvin dellroycd, 

 procefTes are fet up in the parts by which reiteration is ac- 

 complifhed. The ends of the bone arc joined by an offeous 

 fubftance, which gives to the part its original folidity ; the 

 tendon regains its firmnefs and power of refillance ; the 

 mufcle can contradt again and move the points of its at- 

 tachment ; and the furface of the body is covered by a new 

 piece of integument. The funflions of the parts are re- 

 itored ; but the newly formed matter can be always diilin- 

 guifhed from the original compolition of the body, and 

 poffefles a weaker vitality. For, in fome cafes, old ulcers 

 have broken out afrefh, and even fraftures have beeu dif- 

 united in dates of great general debility. A divided nerve 

 is reunited, even if a fmall portion be removed : and the 

 fuuftion of the part, fufpended for a time, is thus reftored. 

 The cafe is different in the blood-ved'els : the proceffes con- 

 fequent on wounds of thefe tend to ftop the hemorrhage, 

 which in general can be effefted only by the obUteration 

 of the tube. 



The power of repairing the effefts of injury is modified 

 by various circumilances. The health and ftrength of the in- 

 dividual, the age, the air, and other circumilances, which 

 the furgeon muft attend to, have great influence. 



In the cafes which have been juft mentioned, the re- 

 ftorative power repairs injuries ; but it goes no further. 

 Neither in man, nor in any warm-blooded animals, are en- 

 tire organs ever reproduced. If a limb be cut off, or a 

 piece of flefli taken away, the wound is healed, the chafm 

 is filled up ; but the loft parts are never formed again. 



In the lower orders of the animal kingdom, on the con- 

 trary, fuch are the ftrength and perfeftion of the repro- 

 duftive energy, that confiderable members are formed again, 

 and we can hardly aflign a limit to the power in fome in- 

 ttances. The lower we defcend in the fcale of beings, the 

 more furprifing are the manifeftations of this repi-oduftive 

 faculty. It is famiharly known, that the claws of the 

 crab and lobfter, and the entire limbs or tail of the newt, 

 can be reftored ; the fame holds good of the rays of the 

 ftar-filh (afterias), and the arms or tentacula of the cuttle- 

 fifh. It was aflerted by Bonnet and Spallanzani, that the 

 entire head of the fnail can be reproduced ; but the afl'er- 

 tion was fufpefted, becaufe other experimcntalifts did not 

 fucceed in repeating the trials. Hence Blumenbach was 

 led to obferve, " that fome experiments on this reproduftive 

 power require a hand exercifed in fuch employments, to- 

 gether with various precautions, and a favourable combina- 

 tion of circumftances, for their fuccefs. Hence perfons 

 muft be cautious in concluding againft the truth of any 

 ftatement, beca\ife their own experiments do not fucceed. 

 After feveral fruitlefs attempts on this fubjeft, I have lately 

 fucceeded in obferving tlie reproduction of the whole head 

 of the fnail (helix pomatia) with its four horns, which oc- 

 cupied about fix months." Comparative Anatomy, tranf- 

 lated by Lawrence, p. 219. 



The fame phyfiologift has given us a remarkable inftance 

 of reprodudlion in an animal of more complicated ftrudture. 

 01 



R.E V 



" I preferve," fays he, " in fpirits a large water newt 

 (lacerta paluftris), from which I extirpated nearly the 

 whole eye feveral years ago : all the humourb were dif- 

 charged, and then four-fifths of the emptied coats were 

 cut away. In the courfe of ten months an entirely new 

 cyc-ball was formed, with cornea, iris, cr)ftalline lens, &c. ; 

 and this is only diftinguifhed from the fame organ on the 

 oppofite fide by being fmaller." Ibid. 



Not only are amputated tentacula fpeedily replaced in 

 the aftinix (fea anemones!, but, if the animal be divided 

 by a vertical or horizontal feftion into two halves, each of 

 thefe becomes an entire aftinia. See the article Anemone. 

 The frefh water polype exhibits very furprifing powers 

 in this way. If it be cut into two or more pieces, thefe 

 become pcrfeft animals. If it be flit half way down, the 

 two halves are rendered perfeft, remaining united below : 

 thefe may be flit again with the fame refuTts. The oppo- 

 fite ends of two polypes may be made to grow together, &c. 

 See Polype. 



See the memoirs on animal re-produftions in Spallanzani's 

 tracts: alfo the works of Bonnet. 



REPROOF, OjsJGiiGATio, in Rhetoric, is diftinguifhed 

 from inveflive ; which fee. 



REPS, in Geography, a town of Tranfilvania ; 16 miles 

 N. of Fogaras. 



REP-SILVER, money anciently paid by fervile tenants 

 to their lord, to be quit of the duty of reaping his corn. 

 REPTILES, in Comparative Anatomy and Phyfwlogy. 

 Although the animals, whofe ftrufture we are about to 

 explain, are perfectly fimilar to each other in their princi- 

 pal charaftcrs, and ought therefore to be united in one clafs, 

 naturalifts have experienced a real difficulty in difcovering an 

 appropriate name for the clafs. That of amphibia, employ- 

 ed by Linnaeus and his difciples, although deduced from a 

 ftrikingcircumftance in the economy of the more generally 

 known reptiles, namely, the power of exifting for a long 

 time in water, as well as in air, is vague and uncertain in its 

 fignification. If we regard as amphibia ihofe aquatic ani- 

 mals, which are able to bve for fome time on land, or thofe 

 land animals, which can remain for a certain time under 

 water, all animals are amphibious ; for even the human fub- 

 jeft and the mammalia can dive. If, on the other hand, 

 the word amphibious be taken etjanologically, and under- 

 ftood to denote an equal power of fubfifling in air and 

 water, it is applicable to no animals. Although reptiles can 

 remain much longer under water than the mammalia, or birds, 

 they are obliged, as their refpiratory organs are only calcu- 

 lated for breathing air, to come fooner or later to the fur- 

 face for this purpofe ; and they are drowned, like any warm- 

 blooded animal, if detained in the water beyond that time. 

 To enable an animal to exift equally in air and water, it 

 fhould have lungs and gills ; that is, it fhould have the power 

 of breathing air, like the mammalia and birds, and of breath- 

 ing water, like filhes ; and it fhould be able to ufe either of 

 thefe methods, to the exclufion of the other. But we know 

 of no fuch animals. The larvs of frogs and falamanders, 

 the proteus anguinus, and the firen lacertina ( fee the latter 

 part of this article), have indeed branchije and lungs ; but as 

 far as our knowledge hitherto goes, none of thefe could live 

 out of the water. The lungs of the tadpole, and of the 

 larvae of falamanders, are defigned for the fervice of thofe ani- 

 mals in their fubfequcnt ftage of exiftence ; but do not give 

 them the power of living in air : and the lungs, either of the 

 proteus or firen, do not feem fufficient to enable them to dif- 

 penfe with the office of the branchial appendages. In its 

 etymological fenfe, then, the term amphibious is not applica- 

 ble to any animals we know of. 



Liniixut 



