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THE TORTOISE-1 



TORTOISES may be divided into thofc that live upon land^ 

 thofe of frefh waters, and thofe of the fea; the former being called 

 Tortoifes, the laft Turtles, but all are amphibious ; the land-tortoife will 

 live in water, and water-tortoifes on land; they are therefore rather 

 named from the refidence they prefer, than from being reftridbed to 

 either. 



Tortoifes, in external form, pretty much refemble each other; their 

 covering is compofed of two great fhells, a fuperior and inferior, only 

 touching at the fides : the ribs, and the fpine of the back, form part 

 of the upper; the lower unites to the fternum. The lower is the leaft, 

 the fofteft, and often almoft flat. Thefe fhells are compofed of feveral 

 pieces, bound together at the edges by very ftrong and hard ligaments, 

 with a fmall (hare of motion in fome kinds. At each end of thefe 

 united fhells is an aperture, one for a fmall head, fhoulders and fore- 

 legs, to pafs through j the other for the hind feet and the tail. Thefe 

 fhells the animal never quits ; but they ferve for his defence, and are a very 

 fubflantial and adequate defence. The upper fhell has commonly thir- 

 teen or fifteen centre-pieces, and a border round them of twenty-two or 

 twenty-five fmallcr. The under fhell has, in Ibme kinds, twelve or four- 

 teen pieces, in others twenty-two or twenty-four. Thefe coverings often 

 weigh four hundred pounds in the marine kinds. 



The tortoile has a fmall head, a little rounded at the muzzle, where 

 are the noftrils ; the mouth is beneath, opens to beyond the ears ; the 

 place of which is fcarcely dillinguiiliabie; no teeth f but two bony ferrated 

 ridges in their place : thefe gather and grind its food. Such is the 

 amazing flrength of the jaws, it is impofTible to open them where they 

 once have faftened ; even, when the head is cut ofF, the jaws flill keep 

 their hold ; and the mufcles, in death, preferve a tenacious rigidity. 

 The legs, though fhort, are inconceivably flrongj and it has been 

 known to carry five men flanding on its back with apparent eafe. 



The blood circulates in this animal, as in fome cartilaginous fifhes, by 

 a very fhort pafTage through the circulation j and the lungs fecm to lend 

 only occafional afTiftance. From this conformation the animal can fubfill 

 fome time without breathing. 



The land-tortoife, from the ufe of its feet in walking, is much more 



nimble on land than the fea-turtle : if thrown oo its back, by rocking 



4 and 



