68 THE VIVARIUM. 
Lizards are found everywhere in the temperate and tropical 
parts of the world. They are either oviparous or ovoviviparous, 
the eggs being covered with a hard or parchment-like calcareous 
shell. Some Lizards lay about forty eggs, others only one or 
two, as the Geckos and the Anoles. 
The teeth of Lizards are either pleurodont or acrodont. The 
pleurodont teeth are those which are attached by their sides to 
a kind of parapet (on the inside) affixed to the jaws. The acro- 
dont teeth are anchylosed or fastened, not in sockets, to the upper 
edge of the parapet. Lizards differ from snakes in having, as a 
rule, eyelids, jaws that do not separate or dislocate at will, and 
throats that are not extensible. 
In many Lizards, such as the Geckos, Lacertide, and Skinks, 
the tail is so brittle that it breaks with the greatest ease, though 
it is reproduced after a time. There is a difference, however, 
especially in the Geckos, between a tail that has been reproduced, 
and one that has never been injured. Some Lizards, like the 
Chameleon, have a prehensile tail. 
For their size, most of these Reptiles are wonderfully quick 
runners, though they are not able to continue their speed for any 
length of time. If anyone should wish to test their swiftness, 
let him take a large Continental Sand Lizard, well called Lacerta 
agilis, and place it at liberty in the midle of a large and closely- 
mown lawn, and then try to catch it. When he has done so, 
I think he will be disposed to agree with my remark above in 
regard to the fleetness of these creatures. There are exceptions 
certainly ; for instance, even a Tortoise can out-pace a Chameleon 
on level ground. 
The Lizards, like the Snakes, desquamate, slough, or shed their 
skins periodically. The former, however, as a rule perform the 
operation piecemeal; while the latter, though they turn their 
cast-off coats inside out, leave them, if the animals be healthy, 
quite entire; and very beautiful objects they are. For some 
days previous to the shedding of their skin, as it is commonly 
called, Snakes cease to feed, but Lizards do not seem to suffer 
much loss of appetite during this period. 
As there are so many different kinds of Lizards, it will, of 
course, be impossible within the limits of these articles to allude 
