270 REPTILIA. 



A third bony ramification, larger than the two others, and directed backwards and down- 

 wards, represents, as in Birds, the coracoid apophysis ; but its extremity remains free. 



The luno-s are much extended, and situate in the same cavity with the other viscera. The 

 thorax being in the greater number immoveable, it is by the action of the moiith that the 

 Tortoise breathes, by holding its jaws firmly closed, and alternately depressing and raising 

 the hvoid bone : the first of these movements permits the air to enter by the nostrils ; when, 

 the tono-ue immediately closing their internal aperture, this second operation forces the air 

 into the lungs. The same mechanism occurs in the Eatrachians. 



Tortoises have no teeth ; but their jaws are invested mth horn like those of Birds, except 

 in the Chelydes, in which they are merelj' covered with skin. Their ear-drum and palatal 

 arclies are fixed to the skull, and immoveable ; their tongue is short, and beset with fleshy 

 papiUffi ; their stomach simple and strong ; their intestines of mean length, and without a 

 coecum ; and they have a very large bladder. The male has a simple penis of considerable 

 size ; and the female produces eggs covered with a hard shell. The male may often be 

 recognized externally, by the concave form of the breast-plate. 



These animals are very retentive of life, and will continue to move for many weeks after 

 having been deprived of the head. They require very little nourishment, and can pass whole 

 months and even years without eating. Linua;us united them all in the genus of 



The Tortoises {Test.udo, Lin.), — 



Which have been divided into five subgenera, principally after the form and teguments of their 



carapaces and feet. 



The Land-tortoises {Testudo, Brongniart) — 



Have a bulged carapace; sustained by a bony skeleton wholly soUd, and anchylosed for the greater 



part to the lateral edges of the breast-plate ; their legs are truncated, with very short toes connected 



almost to the nails, and are capable, together with the head, of being completely withdrawn into the 



armour ; the fore-feet have five nails, and the hinder four, all thick and conical. Several species 



subsist on vegetable matter. 



The Greek Tortoise (T. graica, Lin.), is that which is commonest in Europe. It inhabits Greece, Italy, Sardinia, 

 and (it would appear) al! round the Mediterranean; is rarely a foot long; feeds on leaves, fruit, insects and 

 worms ; and burrows a hole in which it passes the winter : it engenders in spring, and lays four or five eggs 

 resembling those of Pigeons. 



Among the foreign species, there are several in the East Indies of enormous size, measuring three feet and 

 upwards in length. One is more particularly known as the Indian Tortoise (T. ^Hrf^"ea, Vosm.), of a deep brown 

 colour, with the carapace compressed in front, and its anterior border reverted above the head. Others are 

 remarkable for the pleasing distribution of their colours, as the Geometrical T. (T. geomeirica, Lin.), a small 

 species with a black carapace, each scale of which is regularly adorned with yellow lines radiating from a disk of 

 the same colour. A nearly similar but much larger kind (T. radiata) inhabits New Holland. 



Some species (the Pyxu, Bell), have the anterior portion of the mouth moveable, as in the Terrapins ; and 

 others (the Kinixys of the same naturalist) can move the hinder part of their carapace, but we have some reason 

 to suspect that this latter conformation is merely accidental. 



The Emydes, or Freshwater Tortoises {Emys, Brongniart) — 

 Have no other constant characters to distinguish them from the preceding, beyond the further sepa- 

 ration of their toes, which are also terminated by longer nails, and the intervals between them are 

 occupied by membranes, though they grade even in this particular. They also possess five nails hefore 

 and four behind. The structure of their feet adapts them to more aquatic habits. The greater 

 number live on insects, small fish, &c. ; and their envelope is generally flatter than in the Land-tortoises. 



That of Europe (T. europea, Schn. ; T. orbicularis, Lin.), is the most widely diffused, and inhabits all the south 

 and east of Europe as far as Pi-ussia. It attains a length of ten inches, and its flesh is eaten, with a view to which 

 it is fed upon bread and tender herbage ; but it also subsists on insects, slugs, small fish, &c. Marsigni states 

 that its eggs require a year to hatch. The Painted Emyde (T. picta, Schaeff.) is one of the prettiest species, brovtii, 

 with each scale encircled with a yellow riband, more wide in front. It is found in North America among the 

 reeds, upon the rocks, or on the trunks of trees, from which it falls into the water on being approached. There 

 are very many others. 



M. Fitzinger separates, under the name of Chelodina, and Mr. Bell under that of Ilydraspis, those species which 

 have an elongated neck, as Em. longicoUis, Shaw, &c. 



Among the Fresh-water Tortoises may be noticed more particularly, 



