380 
VERTEBRATA. 
or extended, in the manner of a fan, at tlie pleasure of the animal. It measures about two feet 
in length ; it is a bold creature, fighting fiercely when pursued, and always extending its broad 
ruff when in circumstances of irritation or danger. 
A still more remarkable development of the dorsal system is presented by the Flying Dragons, 
of which three species are known in India and the Asiatic Islands. They live on trees, upon 
which they run about in search of insects, on which they feed. These are furnished with a 
broad membraneous lobe on each side, supported by six first false ribs, which are extended straight 
outward from the vertebral column. By the movements of these bones the dragons are enabled 
to stretch their broad lateral membranes, which thus form a sort of parachute to support them 
in long leaps from branch to branch. They are, however, quite destitute of any power to strike 
the air, so that their flight is in fact nothing but a floating through the atmosphere. They 
are small harmless creatures, seldom exceeding a foot in length. 
The flying dragons of the older writers w^ere fabulous creatures, and their descriptions are 
knowTi to have been, in some instances, founded upon articles manufactured for the express pur- 
pose of duping credulous naturalists. 
Some other species of the Agamidse are worthy of notice. Among them we may mention 
the Stellio vulgaris, a common lizard in the Levant, 
and also in Egypt, where its excrements were for- 
merly collected and used as a cosmetic. Cuvier 
states that the jMahometans destroy this animal wher- 
ever they see it, because, as they say, it insults them 
by bowing its head in imitation of their motions when 
engaged in prayer. Another singular species, from 
Australia, has been described by Dr. Gray under 
the name of Moloch horridus. The whole surface of 
this lizard is covered with irregular plates and strong 
acute spines, and the upper surface of the head bears 
two very large spines. Altogether it is a most hideous- 
looking creature. 
Genus PHRYNOSOMA : Phrynosoma.—Th\& in- 
cludes Douglass's Phrynosoma, P, Douglassii, found 
at Salt Lake Valley, by Captain Stansbury, from whose 
work we copy the annexed engraving. It is three and 
a half inches long, and olive-green above. The head 
is covered with sharp spines or roundish knobs; the 
body is scattered over with irregular spine-like scales. 
It is sluggish in its habits, and has some resem- 
blance to a toad, whence this, with other species — 
of which there are five or six, in California, Utah, 
and the Southwestern States — are called Horned 
Douglass's phrtnosoma. Toads. 
THE CHAMELEOKTID^f 
Genus CHAMELEON : Chamceleo. — This is the only genus of the family, but it contains about 
eighteen known species, all inhabitants of the Old World, and which are, perhaps, the most singu- 
lar in the whole order of lizards. They are all small animals, with a curious pyramidal, and 
unusually angular head, distinctly separated from the neck, a short, thick body, which gradually 
tapers from the region of the shoulders to the point of insertion of the hind-legs, and a short pre- 
hensile tail. The mouth is very large ; the teeth are firmly attached to the jaws ; the ears are 
entirely concealed under the skin, and the eyes, which are very large and prominent, are closely 
covered by a circular lid, which is only perforated by a small round opening immediately in 
front of the pupil. The legs are rather long and slender ; the feet are composed of five toes, 
which, however, are divided into two opposite bundles, and the toes of each bundle are so united 
