TORTOISES AND TURTLES. 391 



be completely retracted within tho shell, and the tail is very short. The 

 whole of the hinder region of tlie skull is covered by a bony roof. There is 

 no bony union between the upper and lower sliells ; and in the carapace 

 numerous unossilied spaces remain for a long time, if not permanently. 

 Except during the breeding season, when the females resort to shelving 

 sandy shores for the purpose of laying tlieir eggs, turtles aie inhabitants ot 

 the open sea, where in calm weather tlicy may at times be seen floating 

 placidly on the surface. When on shore, they shuffle along in an awkward 

 manner ; and if turned on their backs are utterly helpless. Their eggs, 

 unlike those of other Chelonians, have soft shells. Like most denizens of the 

 open sea, the three common species of turtles have an almost world-wide 

 distribution. Of these, tho green turtle (Chdone mydas) is the one whose 

 flesh is used for culinary purposes. Nearly allied is the hawksbill (C. imbricata), 

 distinguished at all ages by the strongly hooked beak, and also by the cir- 

 cumstance that, for a considerable portion of life the horny shields of the 

 shell overlap one another like the slates in a roof, instead of meeting at the 

 edges. It is this species alone that yields the tortoise-shell of oonmaerce. 

 More distinct is the logger- 

 head (Thalassochehis caretta), 

 in which the head is of pro- 

 portionately greater size, and 

 there are five, instead of four, 

 pairs of homy costal shields 

 on the carapace. The logger- 

 head is the largest of the three. j,^^ e.-LoGOERnsAD Tokioise 

 It is somewhat remarkable that (Thalassochetys caretta). 

 whereas the green turtle is an 



herbivorous animal, feeding chiefly upon sea-weeds, both the hawksbill and 

 the loggerhead are carnivorous ; the food of the latter consisting largely of 

 cuttle-fish. 



During the egging'- season turtles come ashore in immense numbers, the 

 Seychelles and Bahamas being two of their favourite resorts. While the 

 females are busily engaged in the occupation of laying, and cf covering up 

 their eggs in the sand, the males generally pass the time by quarrelling among 

 themselves. Moonlight nights are those usually chosen for resorting to the 

 coast ; and these, of course, are most favourable to the turtle-catchers, whoso 

 object is to intercept their victims before they can scuttle back to the sea. 

 Not only are the eggs largely used as an article of food, but they also yield 

 an excellent oil. Tortoise-shell, when heated, has the peculiar property of 

 welding like iron, so that plates of almost any size can be obtained by uniting 

 a number of shields. It can also be pressed into moulds, and beautiful 

 amber-like necklaces and other ornamental articles are manufactured from 

 the scraps and fragments. 



Although the huge leathery turtle (Dermochelys coriacea) — the giant of tho 

 tribe — is a marine species with flippers for limbs, yet it diff'ers so markedly 

 from the other turtles in the structure of its shell and the 

 conformation of its skull, that it unquestionably represents Leathery Turtle, 

 a separate family by itself. Indeed, as regards its shell, not — Family 



only does the luth (as this species is sometimes called) diflPer DcrmochdyidcB. 

 from other turtles, but likewise from all other living Chelonia. 

 In place of the carapace being formed by a series of large regularly-shaped 

 bones, some of which are firmly attached to tho backbone and ribs, and all 



