REPTILES. 
289 
the fourth on each side of the lower jaw produced, and received 
into a cavity in the upper one ; feet half webbed, and not den¬ 
ticulated. 
Alligator sclerops — The Alligator. 
Plate LXX. fig. 1. 
Brownish-green above, irregularly marbled; lower parts pale 
sulphur-yellow ; muzzle depressed, slightly tapered, with a cen¬ 
tral ridge; jaws with nineteen teeth on each side; a carinated 
dentated ridge, extending from each shoulder to the point of the 
tail, with a shorter one on each of the sides; upper parts with 
strong regular excavated scales; sides and limbs with reticulated 
and spotted scales ; under parts furnished with transverse plates. 
Twenty feet long. Inhabits the rivers of Brazil. 
TRIBE II.-LACERTINIDiE. 
Genus 4. — MONITOR. — Cuvier. 
Generic Character. —Scales on the head, abdomen, and tail, 
small and imbricated ; tail laterally compressed ; teeth in both 
jaws, but having none on the palate. 
Section I. — Tail flattened with a carinated ridge. 
Monitor variegatus. — The Variegated Monitor. 
Bluish-white, or yellowish-white, variegated with black and 
purple patches, and the tail with annulations of the same co¬ 
lour ; the tail is double the length of the body, round, and a 
little wrinkled on the sides; with a triple plait under the throat. 
Section II. — Tail nearly rounded, with a dentated ridge on 
its upper side. Inhabits New Holland. 
Section III. — Tail nearly rounded, without a ridge. 
Genus 5. —DRACCENA.— Cuvier. 
Generic Character. —Head furnished with angular plates; 
scales on the back large, broad, and carinated, which are strong¬ 
ly serrated on the tail; scales on the throat small; abdominal 
and caudal scales rectangular; tail round at its base, and com¬ 
pressed towards its point; tongue bifid. 
2 A 
