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THE POPULAR SCIENCE MONTHLY.

to be generally felt, and the means to do it will assuredly follow. The colleges seem to be doing too little to advance the sum of knowledge in the direction of biology. Few of them are equipped for research; and in a large proportion of them the professors of biology are handicapped by having other work to do not connected with their department.

 

The Moss Sponge of an Alaskan Forest.—In the interior plateau of the Cordilleran and St. Elias regions of Alaska, according to Mr. C. W. Hayes, surface degradation is greatly retarded by the luxuriant growth of moss, which covers practically the entire surface of the country. The annual precipitation is largely confined to the winter months, and the water from the melting snow is held by the sponge-like moss, which remains saturated throughout the short but hot and dry summer. Thus, with a rainfall which in lower latitudes would condition an arid region, a large part of the surface is swampy, quite irrespective of slope—that is, wherever the material composing it is sufficiently compact to become impervious to water on freezing. On account of this slow and imperfect surface drainage, the slopes are not cut into the ravines and arroyas so characteristic of arid regions.

 

Orography of the Mount St. Elias Region.—From the vicinity of Frazer River, in southern British Columbia, says Mr. C. W. Hayes, in his Expedition through the Yukon District, the western mainland range of the Cordilleran mountain system follows the coast toward the northwest as far as the head of Lynn Canal. Here it becomes an interior range, while to the westward its place next the coast is taken by the St. Elias range. The southern Alaskan coast mountains form a broad elevated belt with many scattered peaks, of which none perhaps have an altitude of more than eight thousand or nine thousand feet, while there is no dominant chain. The southwestern front of the range rises abruptly from the waters of the inland passage, forming a rugged barrier to the interior. A few rivers have cut their channels through the range, and it is penetrated varying distance-by numerous deep fiords. From the head of Lynn Canal northwestward the range decreases in altitude and probably spreads out and merges in the broken plateau which occupies the eastern part of White River basin. The elevation of the interior plateau, where it is crossed in passing from the Taku to Lake Ahklen, is about five thousand feet above sea-level. From this point it descends gradually toward the northwest. Southwest of Selkirk the same plateau extends with gradually increasing altitude to the base of the St. Elias Mountains. It is only in a general way, however, that these areas are to be regarded as plateaus. When considered in detail, the surface is extremely rough and broken. The river valleys lie from two thousand to twenty-five hundred feet below the general plateau level, while broad and rounded dome-like summits and a few sharp peaks rise from seven hundred to twelve hundred feet above it; but there appear to be no well-defined ridges or chains of peaks. For about one hundred and fifty miles southwest of Selkirk the contours are generally smooth and flowing, and the surface, except in the glaciated portion of the region, shows the effect of long-continued exposure to the action of subaërial agencies.

 

The Geological Collection of the National Museum.—In the arrangement of the geological collections of the United States National Museum, as described in Curator George P. Merrill's Hand-book, the wants of the specialist of facilities for study, and those of the public, in whom it is desired to arouse an interest in natural phenomena, have both been consulted. An exhibition is set up of series arranged and labeled for the general public, and accessible at the same time to the student and specialist, and a study series is stored away in drawers. The exhibition series is treated essentially according to the plan given by Prof. Geikie in the latest edition of his text-book on geology; conforming to Mr. Goode's suggestion that a museum should consist of a collection of labels illustrated by specimens, the curator has striven "to build up the exhibition series on the plan of a profusely illustrated text-book, in which the specimens themselves form the illustrations, and the text is furnished by the labels." No object has been intentionally exhibited merely on account of its beauty, rarity, or curiosity