NATURAL HISTORY. 
Ill 
ROOM II.] 
Trigonocephalus. 
( i . Bothrops. 
Trimesurus. 
Tropidolsemus. 
Atropos. 
Megara. 
e. Lachesis. 
Fam. 2. Viper idee, 8. 
a. Cerastes. 
Echis. 
b. Daboia. 
Clotho. 
c. Sepedon. 
d. Pelias. 
Vipera. 
e. Acanthophis. 
B. Innocua. 
Fam. 3. Colubridee, 
9 to 17- 
o.Coronella. 
Lycodon. 
Herpetodryas. 
Coluber. 
Psammophis. 
Tropidonotus. 
Heterodon. 
b. Calamaria. 
Rhinostoma 
Elaps. 
Bungarus. 
Platura. 
c. Naja. 
Hamadryas. 
Xenodon. 
d. Dendrophis. 
Dryophis. 
Langaha. 
Telescopus. 
Bucephala. 
c. Dipsas. 
d. Homalopsis. 
Helicops. 
Hydrops. 
Hypsirina. 
Sect. II. Cata- 
PHRACTA. 
Emyda. 
Fam. 5. Chelonia - 
dee, 23. 
Sphargis. 
Chelonia. 
Ord. III.Chelonia. Order IV. Emydo- 
Fam. 4. Boidee, 18. 
a. Boa. 
Eunectes. 
Epicrates. 
Xiphosoma. 
Helionomus. 
b. Python. 
Liasis. 
c. Gongylophis. 
Eryx. 
Clothonia. 
d. llysia. 
Cylindrophis. 
Fam. 5. Hydridee, 19. 
a. Pelamis. 
Lapemis. 
b. Hydras. 
Liopala. 
Aturia. 
Hydrophis. 
c. Acrochordus. 
Chersydrus. 
Erpeton. 
Bitia. 
Fam. I. Testudini- sauri. 1 & 2. 
dee, 20. 
Testudo. 
Chersina. 
Kinyxis. 
Pyxis. 
Fam. 2. Emydee, 
a. Geoemyda. 
Emys. 
Cyclemys. 
Malaclemys. 
b. Cistuda. 
c. Kinosternon. 
Staurotypus. 
d. Chelydra, 22. 
e. Platysternon, 2 
Fam. Crocodilidee, 24. 
Gavialis. 
Crocodilus. 
Alligator. 
Caiman. 
Order V. Amphis- 
BA2NIA. 24. 
Fam. 1. Trogono- 
phidee. 
Trogonophis. 
Fam. 2. Chirotidee. 
Fam. 3. Chelydee, 22. Earn. 3. Amphisbee- 
Sternotherus. nadea. 
Chelodina. • a , Amphisbaena. 
Hydraspis. Anops. 
Chelys. Blanus. 
Fam. 4. Trimycidee. Lepidosternon. 
Trionyx. Cephalopeltis. 
The Batrachians ( Cases 25 and 26) agree with the reptiles in so 
many of their characters, that they have been very generally believed 
to be only an order of that class; they chiefly differ from them in their 
skin being destitute of scales, their toes without any true claws, and in 
having two occipital condyles. Their heart has only one ventricle and 
a simple auricle, and the blood is cold. They are oviparous; some 
few are ovoviviparous. This class is divided into sections, according 
to the change of form which the animals undergo before they arrive 
at perfection, containing five orders. 
The animals of the first section (called Mutabilia) undergo a dis¬ 
tinct transformation, the young animals being of a fish-like form, 
and furnished with external gills, which eventually fall off when the 
limbs are developed, not leaving any holes or slit on the side of the neck. 
The bones of their skull are only united by membranes. Their eggs, 
which are laid in water and covered with a membrane, are generally 
fecundated and enlarge in size after they are deposited. The young 
usually undergo a transformation before they arrive at maturity, and 
generally have external gills, which they commonly lose when they 
change their external form, but some few, as the Sirens , retain them 
through life. 
This section contains two orders, the Anoures and the Urodeles , or 
Tailless and Tailed Batrachians. 
The Tailless Batrachians (Anoures) are distinguished by the adults 
having a broad short depressed body, quite destitute of any tail. Their 
four limbs are very unequal in length and strength, the hinder pair being 
much the longest. Their skin is quite naked, and the orifice of their 
cloaca is contracted into a rounded form. Their head is large and flat, 
the mouth very large, without any teeth in the lower jaw. They are 
