7 o TORTOISES AND TURTLES. 



found alike in slow or swift-flowing streams, or in open lakes. During the day- 

 time it leaves the water to bask in the sun on sequestered spots of the banks, 

 where it remains without moving by the hour together, but towards sunset it 

 begins to move, and remains active throughout the night. At the commencement 

 of winter it constructs an underground chamber, in which it remains buried in 

 slumber till spring, usually reappearing, if the weather be favourable, about the 

 middle of April ; at which time it reveals its whereabouts by a peculiar whistling 

 cry characteristic of the breeding-season. An excellent swimmer and diver, the 

 pond-tortoise disappears beneath the water at the slightest sound ; while when on 

 land its motions are far more active than those of the true tortoises. Agreeing 

 with other carnivorous terrapins in the absence of a median ridge on the fore-part 

 of the palate, this tortoise feeds chiefly upon worms, water-insects, crustaceans, 

 frogs, newts, tadpoles, and fish. In devouring fish, they reject the air-bladder, 

 which floats on the surface of the water ; and from the number of such floating 

 air-bladders some idea may be formed as to whether a pond is numerously 

 tenanted by these tortoises. In captivity, where they will live for years, pond- 

 tortoises, in addition to their natural food, will readily eat raw meat ; and in this 

 state they frequently become so tame as to take food from the hands of their 

 masters. The eggs, varying from nine to fifteen in number, are laid at night 

 during May in hollows dug by the female in dry soil, at a considerable elevation 

 above the bank, where they are carefully covered up and left to develop. These 

 tortoises are eaten by the inhabitants of all the countries in which they occur. 



The remaining members of this extensive family, which may be 

 collectively known as terrapins, and can receive but brief mention, 

 have the plastron without any transverse hinge, and firmly connected by bone with 

 the carapace, so that the whole shell is solid and immovable. They comprise a large 

 number of species, arranged under eleven genera, and all that can be attempted in a 

 work of the present nature is to select for special notice one or more species of such 

 genera. Although many of these terrapins are exceedingly unlike one another ex- 

 ternally, yet they are all so closely connected that the genera can only be dis- 

 tinguished by the characters of the skull and the bony plates of the shell, so that 

 our description must of necessity be somewhat technical. 



sculptured The sculptured terrapin (Clemmys insculpta), of eastern North 



Terrapin. America, is selected as a fairly well-known representative of a genus 

 of eight species. This genus, it must be premised, forms one of a group of four 

 agreeing with the two last noticed in the absence of a longitudinal ridge on the 

 fore part of the palate, and in the carnivorous habits of its various members. 

 From the three allied genera, Clemmys may be distinguished by the aperture of the 

 inner nostrils in the skull being situated between the eyes, by the unpaired 

 entoplastral bone of the lower shell being traversed by the groove formed by the 

 junction between the humeral and pectoral shields, and by the upper part of the 

 head being covered with a continuous smooth skin. The figured species belongs to 

 a group of five, characterised by the median union of the anal or hindmost shields 

 of the plastron being longer than that between the femoral shields ; and while four 

 species of this group are confined to North America, Beale's terrapin (C. bealei), 

 inhabits China, thus showing a distribution analogous to that of the alligators. On 



