66 
illustrations. Alligators, Caimans, etc., are almost entirely confined 
to tropionl America. All the members of the Crocodilia are born 
from eggs, which are usually deposited in masses of decaying 
vegetation on the margins of the rivers and lakes they inhabit. The 
heat produced in the fermentation helps to bring about the incuba- 
tion of the eggs. Alligators are in most respects similar to crocodiles, 
but the typical member of the latter group is a much more scaly and 
rougher skinned animal than the average alligator. Some crocodiies 
are so much like their congeners and vice-versa, that it is a very 
difficult matter to discriminate between them. If, however, the 
following formula be remembered no further difficulty will be ex- 
perienced in their separation. Close to the front of the lower jaw of 
a crocodile there is a tusk on either side which, instead of being 
covered by the upper j.aw, still shows when the mouth is shut. In 
the upper jaw there is a depression or notch, and it is into this that 
the tusk fits. Alligators invariably lack this dental arrangement. 
Tortoises. — The regularity with which these creatures make 
their appearance in bird-shops during the early summer has made 
them neither feared nor respected. These Grecian Land Tortoises are 
usually purchased to clear the house of “black-beetles," or to rid the 
garden of slugs. Curiously enotigh though this is a popular notion, 
no tortoise of this species has ever been known to prey on either of 
the above pests, not even when dying from starvation, which they 
are too frequently left to do. Instead of clearing the garden of slugs 
they are usually discovered clearing it of lettuce, strawberries, 
etc., as they are confirmed vegetarians. These reptiles have no 
teeth but a very bird-like beak, the jaws closing on one another like 
a pair of scissors. As they are toothless, they do not masticate their 
food but bite off" portions of a convenient size to swallow. The 
carnivorous tortoises tear their victims to pieces with the help of 
their fore-legs. These creatures are born from almost spherical 
hard-shelled eggs which are laid in trenches in the sand. The holes 
are dug out by the hind feet of the tortoise which, after depositing 
the eggs, refils the trench with the dug-out sand and leaves their 
incubation to the sun. With the approach of the cold season these 
reptiles cease to feed, and, burrowing down deeply into the ground, 
they pass the winter in a state of torpor, again waking to activity 
with the return of the warmth of spring. 
Lizards. — This family is by far the most widespread of all the 
reptile groups. Its members are found in almost every country in 
the world which is not embraced by the Polar Regions. They 
inhabit alike dry arid deserts and tropical jungle mar.shes, and 
several races exclusively frequent the higher elevations in moun- 
tainous districts. 
It is this section of the Reptilia which displays the greatest 
diversity in colouration. Most lizards are hatched in the ordinary 
way, but several species are born alive. Our common English 
Lizard is an example of this latter group. Though these reptiles 
are so abundant, only one division comprising but a few species 
contains members capable of giving a poisonous injection. These 
are the American Heloderms which are fortunately never met with 
in the Old World. The outer skin of these reptiles is periodic.ally 
cast, not, as in the case of snakes in one piece, but is shredded off 
as the animals dart in and out the coarse herbage, amongst which 
they live. The illustration on page 32 shows a green lizard 
beginning to slough on the right leg. There is, however, one lizard 
which sheds its coat entire, and that one is the Ulue Lizard o( 
America figured on page 44, 
