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Appendix 
Some iguanids grow up to two meters in 
length. Vision is the predominant sense, as 
in other Iguania, and many species have 
bright colors, and appendages such as crests 
and throat-fans ; some can change color. Dif- 
ference in appearance between male and 
female sometimes marked. Palate sometimes 
toothed. Osteoderms usually absent. Tongue 
broad, scarcely or not at all notched. Nearly 
all oviparous. 
Family Agamidae (agamids) 
Old World counterparts of the Iguanidae, 
but distinguished from the latter by 
acrodont teeth (except often at front of 
jaw) ; palate toothless. No limbless forms. 
Tongue broad, with or without slight notch. 
Oviparous. Known as “dragons” in Austalia 
where there are many genera. 
Family Chamaeleonidae (true chameleons) 
Mostly arboreal Old World lizards, prob- 
ably of agamid descent. Skull usually adorned 
with casque; horns and other appendages 
sometimes present. Teeth acrodont. Palate 
toothless. Osteoderms usually absent. Feet 
with opposible digits. Organ of Jacobson 
rudimentary or absent. Tongue modified for 
capture of prey. Tail prehensile, no 
autotomy. Marked power of color change. 
Mostly oviparous. 
INFRAORDER: Gekkota 
Family Gekkonidae (geckos) 
A very large family of small lizards found 
in warm countries throughout the world, 
prone to introduction in ships, fruit cargoes, 
etc. Head and body usually flattened. Palate 
toothless. Digits often modified for climbing, 
sometimes for movement over sand. Eyelids 
generally fused to form spectacle. Tongue 
broad, with very slight notch. Almost all 
oviparous, laying hard-shelled eggs. 
Family Pygopodidae (snake lizards) 
A small Australasian group of snake-like 
lizards, surface-dwellers or burrowers. 
Palate toothless. Osteoderms absent. Specta- 
cle covering eye. Tongue notched. Oviparous. 
INFRAORDER: Scincomorpha 
(Leptoglossa) 
Family Xantusiidae (night lizards) 
A small New World family of secretive, 
superficially gecko-like forms with normal 
limbs. Palate toothless. Osteoderms probably 
absent. Spectacle over eye. Tongue short, 
barely notched. One genus (Xantusia) is 
viviparous with well-developed placenta. 
Family Teiidae (teids, whiptails) 
A New World family containing some very 
large as well as some very small forms. In 
some genera the body is snake-like and the 
limbs reduced. No osteoderms. Palate usually 
toothless. Tongue forked, and long and pro- 
trusible in Tupinamhis. Mostly oviparous; 
several parthenogenetic species. 
Family Scincidae (skinks) 
A large and cosmopolitan family, mostly 
living on or beneath the ground. Numerous 
genera have reduced limbs. Well-developed 
osteoderms on head and body. Palatal teeth 
sometimes present. Eyelids fused to form 
spectacle in some cases. Tongue fairly broad, 
slightly notched. Oviparous and many 
viviparous species, some with well-developed 
placentation. 
Family Dibamidae (dibamids) 
One burrowing limbless form. Systematic 
position doubtful; differs from burrowing 
skinks in lacking osteoderms. No external 
openings for eyes or ears. 
