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Page:Popular Science Monthly Volume 73.djvu/123

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recently been unpacked, and their study has scarcely more than begun. The shores of the lake, while doubtless steep in places, must have sloped gradually at many points, and there was much shallow water. In this grew the broad-leafed cat-tail of those days, the Typha lesquereuxi. The remains of its leaves are found in the greatest abundance and upon some of them it has even been possible to detect a fungus, which has been called Didymosphæria betheli. In the water near the bases of the cat-tails was a duckweed. Water lilies have not been found; a round water-lily-like leaf proves to belong to a semiaquatic plant, a kind of frog's-bit. A small rush, a species of Juncus, scattered its fruits everywhere. Small fresh-water molluscs, similar to those of the present day, abounded. There were bivalved forms (Sphærium), and representatives of the pond snails Lymnæa and Planorbis. Dragon-fly and May-fly nymphs were excessively numerous, especially the latter; while the adult insects flew along the shore. Minute bivalved Crustacea were in myriads, but no crayfishes have been detected, and there is no reason for supposing that any existed. In slightly deeper water, there were innumerable fishes, and well-preserved specimens of several species have been obtained. From the fish specimens actually secured, one might suppose that these animals were comparatively rare; but this idea is contradicted by the abundance of their excrement, often containing ants and other insects which may have been killed by the volcanic fumes or ash. It would seem, indeed, that at the beginning of an eruption, the fishes gorged themselves with the falling insects; but when things got too hot for them, they mostly retreated in safety to deeper waters, where they escaped entombment. No frogs or turtles have been obtained, much to our disappointment; it is hardly to be supposed that there were none—we may rather anticipate that they will be unearthed by some happy collector of the future. Near the shores, the principal trees were the narrow-leafed cottonwood—differing little from the one common in Colorado to-day—a kind of beech, Fagus longifolia, and a Myrica with slender twigs, which may not have been more than a shrub. A little more distant from the water, perhaps, were the redwoods, Sequoia haydeni, very like those growing in California at the present time. Under or near the redwood grew the incense cedar, a tree now confined to the Pacific coast (where it still grows with Sequoia) and China, though a closely allied genus occurs in the southern hemisphere. There were no firs or spruces, but two or three species of pine trees were plentiful, probably upon the tops of the little hills; and a shrubby or tree-like juniper—like the so-called cedar of modern Colorado—was a conspicuous object. The warmth and dampness of the climate are indicated by an abundance of ferns, such as may be seen in the forests along the Hudson at the present time. Indeed, the whole aspect of the country must have been