Dear Sir

The marine Saurian, which you were asking me about last night, inhabits the Galapagos Archipel:, which is situated under the equator, and about 600 miles from the West coast of America.— M^r Bell has  called the genus Amblyrhyncus,¹ there are two species, both I believe peculiar to these islands; one is of a black colour, with vertically compressed tail; the other yellow & with cylindrical tail, the latter species being confined to the central division of the archipelago.— The islands are all volcanic, and many of the lava streams appear very recent: the aquatic lizard inhabits the coast rocks, even on islets where there is not a drop of fresh water. Although having seen hundred of these animals I never saw one five yards above the sea beach, generally they lie basking by dozens together with outstreched legs on the black basalt, only a few feet above the surf.— They are occasionally seen some way out at sea; but when disturbed on the coast, they do not take to the water, but try to conceal themselves in the crevices.— I conceive this is owing to their habitual enemies, only inhabiting the water.— When thrown into the sea: they swim quickly & with much elegance; their legs are closely collapsed on their bodies, and they proceed by a serpentine movement, like an eel.— They can live for an hour under water.— I opened the stomach of several, & found it distended with quantities of chopped sea weed, a species which I believe generally grows a little way from the beach, on the rocky bottom.— The terrestrial species is likewise herbivorous, feeding chiefly on berries & pieces of Opuntia.— The aquatic amblyrhyncus commonly attain a size between two & three feet; one rather large one weighed no less than twenty pounds.— These hideous creatures are quite harmless and very tame.— I could discover nothing about their propagation.—

This archipelago seems a paradise for the reptile order, (as much as the islands in the time of the Lias were) the land may be said to swarm with huge tortoises the terrestrial amblyrhyncus, small lizards & snakes—whilst the salt-water, with our hideous friends the aquatic Amby: & several species of tortoises.—

I hope you may be able to extract the information you desired out of this untidy account, and believe me dear Sir, | Yours most faithfully | Chas. Darwin 36 Grt. Marlborough St Thursday.—