30 NATURAL HISTORY. [UPPER FLOOR. 
and Agamse. They are only found in the warm parts of 
the Old World. 
The Agames ( Agaviidce , Case 4) present several pe¬ 
culiarities of form, and have therefore been divided into 
many groups. Some have the head lyre-shaped, and the 
back and tail crested ( Gonyocephalus); others have the 
head armed with spines over the back of the ears, and the 
scales large and directed upwards ( Calotes ), which latter lay 
fusiform eggs. The Bronchoceles differ from the Calotes , 
by the scales of the back being small and horizontal; and 
the Acanthosaura has a square head and long subulate 
spines over the eyes. The true Agamse ( Agama ) have 
often bundles of spines on the sides of the neck. The male 
Sitana has a large pouch under the throat, (which is quite 
wanting in the female,) and they have no hinder thumb. 
The Stellio, which was formerly much esteemed for its sup¬ 
posed medicinal qualities, has bands of large spines round 
its tail. The Trapeli or Mutable Agamse, so called from the 
quickness with which they change the colour of their skin, 
are generally armed with irregular, spine-like scales. The 
Molochs of Australia are covered with long conical spines 
surrounded with small spines at their base. They are 
highly coloured, especially on the under side. The 
Earless Agamse ( Phrynocephali ) have the same irregular 
scales as the Mutable Agamse, but they differ from them, 
and all the former, by the drum of their ears being hidden 
under the skin, as in the Chameleons. The Megalochilus 
differs from the former in the margin of the lips being 
spread out and fringed, and the claws very long. The 
Dragons ( Dracones ) differ from all these by the skin of 
the sides being spread out into the form of wings, and 
held up by the end of the ribs. The wings, when the 
animal is at rest, are folded together on the sides of the 
body, but when it leaps from branch to branch they are 
spread out, and act as a parachute; there are several spe¬ 
cies, differing from each other in the length of the throat- 
pouches, and in the colour of the wings. The rest of the 
Agamidce are furnished with a series of minute glands on 
the under side of the hind legs; as the Gemmatophorce , pe¬ 
culiar to New Holland, which have rough scales like the 
Mutable Lizards, and the Lophyri have a crest of large 
scales on the back, which has caused them to be confound- 
