{41}Lizards are much more numerous, and there are several peculiar and interesting forms. Three families are represented; Teidæ by two genera--_Callopistes_ peculiar to Chili, and _Ameiva_ which ranges over almost the whole American continent and is found in Patagonia; _Geckotidæ_ by four genera, two of which,--_Caudiverbera_ and _Homonota_--are peculiar to Chili, while _Sphærodactylus_ and _Cubina_ are Neotropical, the former ranging to Patagonia, the latter to Chili; and lastly the American family Iguanidæ represented by eight genera, no less than six being peculiar, (or almost so,) to the South temperate region. These are _Leiodera_, _Diplolæmus_ and _Proctrotretus_, ranging from Chili to Patagonia; _Leiolæmus_, from Peru to Patagonia; _Phrymaturus_, confined to Chili, and _Ptygoderus_ peculiar to Patagonia and Tierra del Fuego. The other two genera, _Oplurus_ 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_, _Cyclorhamphus_, _Pleurodema_, _Cystignathus_, and _Leiuperus_, are found in various localities, some extending even to the Straits of Magellan,---the extreme southern limit of both Reptilia and Amphibia, except one lizard (_Ptygoderus_) found by Professor Cunningham in Tierra del Fuego. There are also four peculiar genera, _Rhinoderma_ belonging to the Engystomidæ; _Alsodes_ and _Nannophryne_ to the Bombinatoridæ; _Opisthodelphys_ to the Hylidæ; and _Calyptocephalus_ to the Discoglossidæ. It thus appears, that in the Reptiles 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 Bombinatoridæ are indeed Palæarctic, but a larger proportion are Neotropical, and one genus inhabits New Zealand. The Chilian genus _Calyptocephalus_ is allied to Australian tropical genera. {42}The Neotropical genera of Ranidæ, five of which extend to Chili and Patagonia, belong to a division which is Australian and Neotropical, and which has species in the Oriental and Ethiopian regions.