_Reptiles._--The few reptiles found in these islands are very interesting. There are two snakes, a species of the American genus _Herpetodryas_, and another which was at first thought to be a Chilian species (_Psammophis Temminckii_), but which is now considered to be distinct. Of lizards there are four at least, belonging to as many genera. One is a species of _Phyllodactylus_, a wide-spread genus of Geckotidæ; the rest belong to the American family of the Iguanas, one being a species of the Neotropical genus _Leiocephalus_, the other two very remarkable forms, _Trachycephalus_ and _Oreocephalus_ (formerly united in the genus _Amblyrhynchus_). The first is a land, the second a marine, lizard; both are of large size and very abundant on all the islands; and they are quite distinct from any of the very numerous genera of Iguanidæ, spread all over the American continent. The last {33}reptile is a land tortoise (_Testudo nigra_) of immense size, and also abundant in all the islands. Its nearest ally is the equally large species of the Mascarene Islands; an unusual development due, in both cases, to the absence of enemies permitting these slow but continually growing animals to attain an immense age. It is believed that each island has a distinct variety or species of tortoise. _Insects_.--Almost the only insects known from these islands are some Coleoptera, chiefly collected by Mr. Darwin. They consist of a few peculiar species of American or wide-ranging genera, the most important being, a _Calosoma_, _Poecilus_, _Solenophorus_, and _Notaphus_, among the Carabidæ; an _Oryctes_ among the Lamellicornes; two new genera of obscure Heteromera; two Curculionidæ of wide-spread genera; a Longicorn of the South American genus _Eburia_; and two small Phytophaga,--a set of species highly suggestive of accidental immigrations at rare and distant intervals. _Land-Shells._--These consist of small and obscure species, forming two peculiar sub-genera of _Bulimulus_, a genus greatly developed on the whole West coast of America; and a single species of _Buliminus_, a genus which ranges over all the world except America. As in the case of the birds, most of the islands have two or three peculiar species.