Page:Popular Science Monthly Volume 10.djvu/259

Rh By E. T. Cox. Pp. 600. Indianapolis Sentinel print.

Public Libraries in the United States. Part I., pp. 1222; Part II., pp. 89. Washington: Government Printing-Office.

Essays in Literary Criticism. By R. H. Hutton. Pp. 344. Philadelphia: J. H. Coates. Price, $1.50.

Vaccination as a Preventive of Small-pox. By W. C. Chapman, M.D. Pp. 91. Toledo, Ohio: Brown & Faunce.

German and American Brewers' Journal. Semi-monthly. $5.00 per year. Brewers' Publishing Company, 20 Park Place, New York.

On Cephalization. By James D. Dana. Part V., pp. 7. From American Journal of Science and Arts.

Report of the Condition of the Academy of Natural Sciences of Philadelphia. By W. S. W. Russhenberger. Pp. 56. Philadelphia: Collins print.

Essential Piety of Modern Science: a Sermon. By J. W. Chadwick. Pp. 31. New York: Somerby.

Surface Drainage of the Metropolitan (Boston) District. By C. W. Folsom, C. E. Pp. 4. From Report of Massachusetts Board of Health.

A List of Orthoptera. By Dr. Cyrus Thomas. Pp. 20. From Proc. D.A.N.S., vol. i.

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Distribution of Plain, Prairie, and Forest.—In the American Naturalist for October, Prof. J. D. Whitney gives a very elaborate critique of the various hypotheses which have been put forth to account for the distribution of plain, prairie, and forest, over the North American Continent. The author has no theory of his own to offer, but he appears to show conclusively that none of the accepted theories can be regarded as satisfactory. One of the theories examined by Prof. Whitney is that which attributes the existence of forest, prairie, or plain, to the distribution of rainfall throughout the year, or from season to season. As stated by the late J. W. Foster, this theory holds that "wherever the moisture is equable and abundant, we have the densely-clothed forest; wherever it is unequally distributed, we have the grassy plain (prairie); and where it is mostly withheld, we have the inhospitable desert." This last proposition Prof. Whitney admits, the other two he pronounces erroneous. He cites the vicinity of Chicago, where Mr. Foster lived, in proof of the incorrectness of that author's views. "Here," says Prof. Whitney, "we have the finest prairie-regions in the world, absolutely destitute of trees, and yet in the full enjoyment of an abundant precipitation, and in the immediate vicinity of an immense sheet of water. For Chicago itself, indeed, the statistics of rainfall are very defective, but, such as they are, they are entirely unfavorable to Mr. Foster's hypothesis. Points in the immediate vicinity of that city, where observations have been taken for a series of years, show an average rainfall of thirty-six to fifty inches, pretty uniformly distributed through the year. An excellent instance, on the other hand, of a dense growth of trees combined with the most unequally-distributed rainfall which is possible, is furnished by the western slope of the Sierra Nevada, in California, whose magnificent forests are well known, as also is the fact that there is no precipitation there at all for six months of the year, nearly the whole of the rainfall being limited to three months. And, lest it may be thought that melting snow keeps the ground moist during the summer, it may be added that the heaviest forest-belt of the Sierra is quite below the line above which snow rests for any considerable time, and that the soil in that belt is usually perfectly dry at the surface, and even dusty, for six months of the year, and often much more."

Electrical Phenomena exhibited by Venus's Fly-Trap.—The electrical phenomena exhibited by Dionæa muscipula have been investigated by Dr. Burdon-Sanderson, who finds that normally the whole leaf with the petiole is somewhat negative, but, when excited by a stimulus, an electrical 