Page:Popular Science Monthly Volume 42.djvu/299

Rh ventilation of the hall of the old Brooklyn Institute was nearly perfect, and was all through large openings in the ceiling.

Life on Mount Roraima.—Mount Roraima, in British Guiana, which was first ascended in 1884 by Mr. Everard Im Thurm, was again climbed in November, 1891, by Mr. E. Cromer and Mr. Seyler, two collectors of orchids. Exploring the top, the adventurers found toward the south many gigantic and marvelously shaped rocks that seemed to form, as Mr. Cromer described them, "majestic palaces, churches, and fortresses." Other smaller rocks resembled pyramids, umbrellas, and kettles, and one bore a striking likeness to the statue of a man. Between these grotesque masses of rocks were innumerable lochs, some joined together by canals, most of which were shallow, although here and there a depth of six feet was found. Many new species of orchids and other plants were found; but the mountain-top seemed almost destitute of animal life. Mr. Cromer noticed one black butterfly, a few spiders, some small frogs, some small lizards, and a small, dark-colored mammal, which he supposed was a species of kibihee, and on his approach gave a sound like a whistle, and swiftly crept into a hiding-place between the rocks. The lakes on the summit, which cover a considerable area, were swarming with a sort of black beetle. Mr. Cromer and his companion are the first men who have stayed a night on the top of Roraima.

The Mentone Skeletons.—The grottoes of Baussé Roussé, or of Mentone, as they are commonly called, are nine in number, and seven of them were inhabited by Quaternary man. M. E. Rivière, who owns them, explored certain of them in 1872, 1873, and 1875, and recovered several human skeletons and interesting relics from them. A second entry was made into one of them, the Barma Grande, last winter, during the owner's absence and without his knowledge, and several other skeletons and relics were obtained in it. Of the two which have been most fully excavated one is the skeleton of an old man, and the other of a young man of about eighteen years of age. They both appear to be of the Cro Magnon race, and are of fairly large stature. They were adorned with collars of sea-shells, bored for stringing, and of canine teeth of the deer, and vertebræ of fish (salmon and trout). The skeletons, shells, teeth, and vertebræ are all colored a curious red, dotted with bright points, which is derived from the dust of specular iron, with which the bodies of the adults were covered immediately after death. The arms and utensils found immediately in contact with the skeletons consisted of a cut flint seventeen centimetres long by fifty-one millimetres broad, which was situated behind the head of the old man, a scraper, and a curious article of bone or deer horn in the shape of a double ovoid, marked on the surface with numerous irregular and irregularly spaced striæ.

Distribution of Land-shells.—Land-shells, according to Mr. W. H. Dall's Instructions for collecting Mollusks, are found at all elevations, from the beaches moist with sea-spray to the Alpine heights of fourteen thousand feet in the vicinity of perpetual snow. Some are subterranean in their habits, pursuing earth-worms through their burrows, or nestling in the recesses of bones in ancient graveyards. Others are contented with the protection afforded by dead leaves, decaying logs, under the bark starting from rotten stumps, or in the shelter of loose stones and bowlders. Other groups live on the leaves of sedges, grass, and shrubbery, retreating to the soil for winter quarters; some highly colored species live permanently in the tree-tops of tropical forests. In arid regions they seek the shade of stones, attach themselves to the stems of cacti or other desert plants, or even adhere to the sunburned surfaces of rocks so hot as to be uncomfortable to the touch. The color of the shell bears a certain relation to its favorite station. The tree-living forms are brightest and most varied; the moss-lovers and terrestrial species are usually dull, horny, or greenish, but often have a brilliant, polished, or delicately sculptured surface; while subterranean forms are pale or pellucid. The slugs are generally nocturnal, and retreat to holes and crevices. In general, limestone regions are most favorable for land-shells, and those of flinty rock least advantageous. Woods of resinous trees are unsuited to their tastes, while soft woods of deciduous trees are congenial to them. Some