[Sixteen or seventeen species of Chameleon are described in the British Museum Catalogue.
I. Having an erect fin on the back, the belly crested; which includes the Fringed Chameleon, C. cristatus, a native of Fernando Po.
II. Having the back high, and compressed belly and sides, with a toothed crest; including the Side-crested Chameleon, C. laterales, a native of Madagascar.
III. The back and belly having a toothed crest, the sides simple, the scales small and equal, muzzle simple; including the Common Chameleon, C. vulgaris, with many synonyms. It is a native of the East Indies, is the recognised type of the family ([Fig. 32]), and the one most commonly brought to England. There are probably two varieties,—one from North Africa, which is also found in Sicily and the South of Spain; the other, the East Indian variety—C. Senegalensis, the Senegal Chameleon, a native of West Africa; C. arpelis, from Ashantee and Gaboon; C. verrucosus, a native of Bourbon and Madagascar; the Rhinoceros Chameleon, C. rhinoceroceratus, also from Madagascar.
IV. Having a toothed crest on the back, with the belly and sides simple, the chin and muzzle simple; including C. tuberculiferus, a native of South Africa; C. cucullatus, the Hooded Chameleon, a native of Madagascar; C. nasutus, having the chin simple, and the muzzle compressed, and C. bifurcus, having the muzzle in the male forked—both natives of Madagascar; C. Tigris, Seychille Islands; C. ventralis, from South Africa, and C. pumilus, from the Cape of Good Hope.
Fig. 32.—Chameleo vulgaris.
V. Having back and belly without crest; including C. Parsonii, a native of Madagascar; and C. Owenii, the Three-horned Chameleon, from Fernando Po, and C. Brookesianus, an adult species, from S. W. Brookes's collection.
Emydosaurians
Have the head large, covered with a thick skin, ears closed with two valves, gape very wide, tongue short, jaws with a single series of cone-shaped teeth inserted in sockets; back with a hard disc formed of a longitudinal series of square keeled plates of hard bony consistence embedded in the skin; the under surface covered with smooth thin square plates; legs short, feet webbed, with four to five toes, the three inner toes of each foot only armed with claws.