6 
The Freshwater Tortoises (Emydid@) have 
more resemblance to marine turtles, The carapace 

Skeleton of Tortoise. 
(back-plate) and plastron (breast-plate) are both flat- 
tened, but are generally ossified, though the head and 
legs are not retractile. : 
short, and the toes distinct, though webbed. There 
are five on the fore feet, and four on the hind feet. 
The water-tortoises are active creatures, living in 
streams and swamps, and feeding on fish and plants. 
The head is long, the legs | 

Fig. d. The Common River Tortoise (Zmys 
europea) inhabits a great part of Southern and Central 
Europe. Its carapace is oval and the colour is dark 
grey with yellowish-white streaks which radiate in 
all directions on each plate. Tortoises hibernate in 
winter in the mud. 
The Sea Turtles (Chelonitd@) are good swimmers 
and pass most of their lives in the water, except 
when they come to the shore to lay their eggs on 
sandy coasts. The carapace is small and pointed 
at the end, and only covers the body. The head 
is flat, the jaws sharp and beak-like and the neck 
short. The four legs end in undivided paddles. The 
toes are scarcely to be distinguished, and are often 
wholly without claws. The Turtles are of a large 
size, and feed on seaweeds and various marine 
animals. 
Plate VIII. fig. a. The Green Turtle (Chelonia 
midas) inhabits the tropical seas, and when full-grown 
it measures six feet in length and weighs 700 Ibs. 
The muzzle is obtuse and the plates of the carapace 
do not overlap. The flesh and eggs are excellent, 
and form a regular article of trade. 
Fig. c. The Hawk's Bill Turtle (Caretta im- 
bricata) furnishes the best tortoiseshell. The horny 
scales of the carapace overlap like slates on a roof. 
The tail is scaly and the upper jaw is notched and 
hooked. This species feeds on various marine 
animals, and not on seaweed like the Green Turtle 
and to this is ascribed the inferiority of its 
flesh. It inhabits the tropical seas of both hemi- 
spheres, 
Class Amphibia. 
The Amphibia are animals with cold red blood, | with small teeth, and they are without ribs. After 
imperfectly divided auricles, but only a single ven- 
tricle. Their skins with few exceptions are naked 
or warty. The limbs are generally well developed, 
but the toes are not clawed. 
The Amphibia are divided as follows: 
the young have left the egg they undergo metamor- 
phoses which particularly affect the respiratory organs. 
All the Amphibia are carnivorous in the perfect state, 
Their jaws are armed | feeding on worms, insects, slugs, &c. 
Anoura. ‘Tail and gills lost in course of metamorphosis, 
Order I. 
,, Il. Urodela. Tail retained, but gills lost. 
,, Ul. Lchthyoidea. Gills and tail retained. 
, 1V. Afoda. Limbs and tail absent. 
Order J. Anoura. 
(Frogs and Toads.) 
(Plate VII.) 
In adult animals the body is short, broad and 
tailless, with four limbs, of which the hind pair are 
the longest, being adapted for leaping and swim- 
ming, and the toes are generally webbed. The muzzle 
is rounded, and the gape wide. The tongue is gener- 
ally fixed in front and free behind, and is adapted 
to seize insects. These. are swallowed whole, for 
tecth, if present are only used to hold them. The 
lungs are elastic air-cavities, and are usually connected 
in the male with a single vocal sac (or sometimes 
a pair) situated in the throat. They are good 
swimmers and divers, and move on land by leaping. 
At the beginning of winter they bury themselves in 

the mud, and remain there without eating or breath- 
ing. In the spring, when the spawning season begins, 
they emerge from 
their hiding places 
and become very 
lively. The spawn 
is laid in shallow 
water either in 
strings (as in the 
toads) or inlumps 
(as in the frogs) 
and when the young, which are called tadpoles, 
are hatched, they undergo the changes shown in 

Skeleton of Frog, 
