114 ORIGIN, ETC., OF THE FAUNA. 
The family Amphisbenide comprises burrowing Lizards, with limbs reduced or 
absent; the majority of the genera are neotropical or African, but the most 
generalized genus, and the only one with fore limbs, Chirotes, is found in California 
and Mexico, and the least specialized of the rest, Blanus, inhabits the countries round 
the Mediterranean. Moreover, Rhineura of Florida is known to date back to the 
Oligocene of Dakota. Here an American distribution similar to that of the Teiide 
is coupled with indications that the group may have been originally a northern one 
that migrated southwards into Africa and South America. 
The Scincide, widely distributed in the Old World, have in all probability reuchnd 
America quite recently, as the three genera found in America are also Asiatic. 
Eumeces has several North American species, and extends southward over the plateau to 
southern Mexico. Lygosoma laterale of the southern United States ranges southward 
to southern Mexico, and in Guatemala is replaced by the closely related L. assatum. 
L. laterale is almost identical with Z. reevesi of China and Burma, and it may be that 
in the warmer climate of Pliocene times the ancestral type ranged northward to the 
land connecting Asia with America, The third American genus, Mabuwia, is found 
also in Africa and southern Asia; there is an Antillean species, one from Costa Rica, 
and four from South America, one of these extending northward to Yucatan and 
southern Vera Cruz. This neotropical distribution of a genus that in all probability 
came through North America parallels that of Zapirus. 
The Iguanide are American, except for two genera in Madagascar and one in the 
Friendly and Fiji Islands. They are also known from the Eocene of Europe, and are 
evidently an ancient group of former wide distribution; the presence of two peculiar 
genera in the Galapagos suggests their antiquity in South America. The South 
American genera are numerous; the majority are restricted to South America, but 
some are also Antillean, and some extend through Central America as far as southern 
Vera Cruz; there are also two or three genera peculiar to Central America. ‘There 
are about ten genera in the south-western United States, some with species on the 
Mexican Plateau and the western Sierra Madre. One species of Uta (U. bicarinata) 
is found on the plateau and also on the west coast from Presidio to Tehuantepec. 
Sceloporus and Phrynosoma are important genera that range from the southern United 
States to Central America, and include species on the plateau as well as in the 
lowlands. 
The Geckonide are found in all tropical countries; in America they are almost 
entirely neotropical, and are not found on the Mexican plateau. ‘The Geckonide are 
peculiarly liable to accidental dispersal, and this is well illustrated by the distribution 
of Gehyra mutilata ; it is found on the islands of the Indian Ocean and the Malay 
Peninsula and Archipelago eastward to New Guinea, but it is also known from 
Western Mexico. The small family Eublepharide, specialized Geckos, includes three 
species from Africa and India, distinguished by their stout form and by their enlarged 
