NATURAL HISTORY. 
33 
ROOM X.] 
have simple toes : the third ( Anolis ) has a simple flat head, 
but the penultimate joint of the toes is dilated on the sides 
into a pear-shaped disk, so as to enable these animals to 
walk on smooth and nearly perpendicular surfaces; of this 
genus there are many species.—Lastly, the marbled Lizards 
{Polychrus) have neither dilated toes nor any dorsal 
crest. 
In the lower part of this Case (No. 3) are the Geckos, 
nocturnal Lizards, of a dull, lurid appearance, with 
depressed heads, and large round eyes. Their body 
is usually covered with small scales, amongst which are 
frequently larger tubercles ; and the under side of their 
toes is generally furnished with variously shaped, imbri¬ 
cated scales, or folds of the skin, which enable the animal 
to crawl up glass, and even to run with facility, the back 
downwards, on the ceiling of a room, like a fly. They are 
found in all parts of the world, and are divided into many 
groups, according to the form of their toes. Some of the 
most peculiar are the Common Gecko ( Gecko guttatus), 
from India ; the Chinese Gecko ( Gecko Revesii ), from 
China ; and the Ornamented Gecko ( Gecko orncitus ), from 
the Isle of France. All these have only a single trans¬ 
verse series of scales, on the under side of each toe. Hard- 
wicke’s Gecko ( Eublepharis Hardwickii) differs from the 
former, by the toes being more slender, and less dilated ; 
one of the species, Horsfield’s Gecko ( Pleropleura Hors- 
field'd) which lives in the ponds in Java, has the skin on 
the side of the chin, body, limbs and tail dilated into a 
kind of fin. 
Many of the species of these Lizards, from their lurid 
appearance, are considered as poisonous by the natives of 
India, and some even assert that they infect every sub¬ 
stance which they walk over, but this is, at least, ex¬ 
tremely doubtful. 
Other species have the scales under the toes divided by 
a central groove, into which the claws are retractile '{The- 
cadactyli). One of these, the Smooth Sheath-claw {Gecko 
Icevis), has many scales under the toes, and on being 
caught, the animal, in its exertion to escape, often casts of 
its tail. It does the same if thrown alive into spirits, in 
which case the separated tail contracts, and assumes an 
almost globular shape, and is most usually found in this 
c 3 
