Antiquity of Man.

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vague; for who will pretend to say that there may not have been several periods of subsidence intercalated between the movements of elevation? for we know that along the whole coast of Patagonia there have certainly been many and long pauses in the upward action of the elevatory forces."

Galapagos Islands-Number of Craters-Gigantic Tortoises-Land and Marine Lizards-New Marine Forms-Flora-Number of Cryptogamic Plants-Variety of Forms on the Different Islands

-Tameness of the Birds.

N the month of September the Beagle crossed the line again, this time on the Pacific side, and cast anchor among the islands of the Galapagos Archipelago, that are simply a group of oceanic craters that have forced their way up through the ocean here, and in the course of time attained a somewhat limited fauna and flora.

The islands Darwin found were all volcanic rock, some of the craters which he visited being of vast dimensions, rising three or four thousand feet, their sides pierced with small but ancient orifices from which in the olden time lava had flowed. A some

Gigantic Tortoises.

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what careful estimate made by him resulted in showing that in the entire archipelago there were probably not less than two thousand craters. On Chatham Island Darwin camped, surrounded by black truncated cones, which were so numerous that he counted sixty from one spot.

As the name suggests, the islands are called after the large tortoises which abound there, and it was not long before several were found by Darwin, who estimated their weight at two hundred pounds each. One was feeding upon some cactus and hardly noticed him. Some of the tortoises attained to large size, specimens being heard of which required eight men to lift and afforded two hundred pounds of meat alone.

One of the first peculiarities on Chatham Island noticed by the naturalist was the lanes and paths which led in every direction. These were the trails worn by the island giants. The springs to which the animals were obliged to crawl for water were situated in the interior, and here he had an opportunity to watch them wallowing about and covering themselves up in the mud.

To test the speed of the turtles, Darwin watched one for some time, and found that it walked at the rate of one hundred and eighty feet in ten minutes, or 1,080 feet in an hour, or at a rate of four miles per day. To show the strength of the animal, he states that he frequently stood upon the back of one and struck it, whereupon it would move away, generally throwing him off.

Chatham Island and its life had a peculiar interest