CHAP. XIV.] 
THE NEOTROPICAL REGION. 
41 
Lizards are much more numerous, and there are several pecu- 
liar and interesting forms. Three families are represented ; 
Teidee by two genera — Gallopistes peculiar to Chili, and Ameiva 
which ranges over almost the whole American continent and is 
found in Patagonia ; Geckotidse by four genera, two of which, — 
Gaudiverbera and Homonota — are peculiar to Chili, while Sphce- 
rodactylus and Gubina are Neotropical, the former ranging to 
Patagonia, the latter to Chili ; and lastly the American family 
Iguanidee represented by eight genera, no less than six being 
peculiar, (or almost so,) to the South temperate region. These are 
Leiodera, Diplolcemus and Prodrotretus, ranging from Chili to 
Patagonia ; Leiolcemus, from Peru to Patagonia ; Phrymaturus , 
confined to Chili, and Ptygoderus peculiar, to .Patagonia and 
Tierra delPuego. The other two genera, Opiums and Leiosaurus , 
are common to Chili and tropical South America. 
Tortoises appear to be scarce, a species of Hydromedusa only 
being recorded. Of the Amphibia, batrachia (frogs and toads) 
alone are represented, and appear to be tolerably abundant, 
seventeen species having been collected by Mr. Darwin in this 
sub-region. Species of the South American genera Phryniscus, 
Hylaplesia, Telmatobius , Cacotus , Hylodes, Gyclorhcimphus, Pleu- 
rodema, Gystignathus , and Leiuperus, are found in various locali- 
ties, some extending even to the Straits of Magellan, — the 
extreme southern limit of both Beptilia and Amphibia, except 
one lizard (. Ptygoderus ) found by Professor Cunningham in Tierra 
del Fuego. There are also four peculiar genera, PMnoderma 
belonging to the Engystomidae ; Alsodes and Ncmnophryne to the 
Bombinatoridae ; Opisthodelphys to the Hylidse ; and Galyptoce- 
phalus to the Discoglossidse. 
It thus appears, that in the Keptiles all the groups are typically 
American, and that most of the peculiar genera belong to families 
which are exclusively American. The Amphibia, on the other 
hand, present some interesting external relations, but these are 
as much with Australia as with the North temperate regions. The 
Bombinatoridae are indeed Palaearctic, but a larger proportion are 
Neotropical, and one genus inhabits New Zealand. The Chilian 
genus Calyptocepkalus is allied to Australian tropical genera. 
