88 
ROOM X. shields somewhat like those on the belly. They are 
Nat. Hist, found in China and Java, and are said to run with 
amazing velocity. Most of these animals have the 
faculty of reproducing their tails when broken off, an 
accident which often happens in the mere exertion of 
the animal to escape. The reproduced part has only 
a central cartilage in the place of the bones, and is 
often covered with scales, different from those of the 
rest of the tail. If the tail be cracked only on one 
side, and not thrown off, a new tail often springs out 
of the crack, so that the member becomes forked. A 
specimen of a Lizard with such a tail, may be seen in 
this Case. 
Cases 3 and 4 contain those Saurian Reptiles which 
have short contractile tongues, slightly notched at the 
end. 
The first of these are the Iguanas, which have their 
teeth attached to the inner edge of the jaw-bone, and 
mostly lobed and indented. They are all found in 
America. 
Some of the Guanas have a compressed dewlap 
under the throat, and the back crested; among, which 
are the common Guana ( Iguana tuber culata ), which is 
used both for food and medicine in the West Indies, 
and the banded Guana ( Iguana fasciatd ). 
Other species of this genus haye only a fold across 
the throat, as the Spiny-tailed Guana (Iguana acan- 
thura), Clouded Guana (Iguana nubila), Sword-tailed 
Ophyessa (Ophyessa superciliosa), Umber Ophyessa 
(O. plica), Collared Tropidurus (Tropidurus tor- 
quatus), Keeled Leiocephalus (Leiocephalus carina- 
tus), Northern Tropidolepis ( Tropidolepis undula - 
tus), Collared Tropidolepis (T. torquatus), Doug¬ 
lass’s Toad-Lizard (Phrynosoma Douglassii), and 
Blainville’s Toad-Lizard (P. Blainvillii). These 
animals are very quarrelsome, and fight with great 
ardour when they meet. 
In other species of Guanas, the ribs surround the 
body 
