Page:Popular Science Monthly Volume 26.djvu/382

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it a long time, had it not moved, before I would have noticed it. I called the attention of the captain of the ship to the object, and he examined it for some minutes, the crab not moving, before he saw anything but bark. How came this brown crab, on a piece of wood of precisely the same color, in the middle of the ocean? Must we believe that several crabs got on the bark, among them the brown one, and that the struggle for existence resulted in his being the only one left? I am satisfied that we can come to no other conclusion than Wagner's, and that we must believe that a conscious or perhaps an instinctive choice governed the animal in settling upon an object so like it in color. The bark was probably occupied while floating among the sea-weed, then drifted away to the spot where it was found, and where it furnished so singular an isolated example of selective mimicry. I found numerous slender fishes in the algae of the Sargasso Sea, likewise protected by their resemblance in color to the plants among which they lived. One afternoon, after I had examined a plant for an hour for crabs, I took it out of the pail to throw it into the sea, when a fish about the size of a lead-pencil fell out of it. I put the fish into another pail, in which there was also a sea-weed. It instantly vanished from my sight, and I had to look for some time among the thick stems before I could find it again.

I do not know whether any of these observations have been recorded before. During my residence in Brazil, I had but limited opportunities to keep acquainted with recent zoological literature. But I found my sail through the Sargasso Sea full of interest, and I believe that a voyage there would be fraught with pleasure and profit to every naturalist. It is not so very expensive, either; and can easily be made on a schooner or bark sailing from a European port to the West Indies. My passage from Porto Allegro in Southern Brazil, to Falmouth, England, from the 15th of June to the 25th of September, cost me, board included, less than seventy-five dollars. Such a voyage furnishes, moreover, at the same time, an opportunity to make a personal acquaintance with the natural history of tropical regions.—Translated for the Popular Science Monthly from Kosmos.



BEFORE proceeding further, I must fulfill the promise made in No. 39 to report the results of my repetition of the Indian process of preparing samp. I soaked some ordinary Indian corn in a solution of carbonate of potash, exceeding the ten or twelve hours