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In certain species of whales there is a tendency to the formation of irregular little points of horn on the palate; and it seems to be quite within the scope of natural selection to preserve all favourable variations, until the points were converted, first into lamellated knobs or teeth, like those on the beak of a goose then into short lamellae, like those of the domestic ducks and then into lamellae, as perfect as those of the shoveller-duck and finally into the gigantic plates of baleen, as in the mouth of the Greenland whale.
There are observed, in the same hollow, small portions of quartz incrusted with an impure salt, and nodules of clay extremely compact. Near the edge of the valley there lie scattered on the sand considerable portions of flinty slate; and amid the common clay, which forms the basis of the soil, are perpendicular layers of a lamellated brown argil, assuming, as it were, the slaty structure. Dr.
To the schists succeeded gneiss, partially stratified, remarkable for the parallelism and regularity of its lamina, then mica schists, laid in large plates or flakes, revealing their lamellated structure by the sparkle of the white shining mica.
I hope that I may not be misconstrued into saying that the progenitors of whales did actually possess mouths lamellated like the beak of a duck. I wish only to show that this is not incredible, and that the immense plates of baleen in the Greenland whale might have been developed from such lamellae by finely graduated steps, each of service to its possessor.
Here also appeared the great oak with lamellated acorns, which I had not seen in the drier valleys to the westward; with many other Dorjiling trees and shrubs. A heavy mist clung to the rank luxuriant foliage, tantalizing from its obscuring all the view. Mica schist replaced the gneiss, and a thick slippery stratum of clay rendered it very difficult to keep one's footing.
In answer, it may be asked, why should not the early progenitors of the whales with baleen have possessed a mouth constructed something like the lamellated beak of a duck? Ducks, like whales, subsist by sifting the mud and water; and the family has sometimes been called Criblatores, or sifters.
The mast of the forest is formed of: Three species of oak, of which Q. annulata ? with immense lamellated acorns, and leaves sixteen inches long, is the tallest and the most abundant. Chesnut. Laurineae of several species, all beautiful forest-trees, straight-holed, and umbrageous above.
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