Page:Popular Science Monthly Volume 47.djvu/584

570 animals, and in it white potatoes, turnips, beets, the Oldberg apple, and the more hardy cereals may be cultivated with moderate success. In the Transition zone, the outlying boreal and austral elements overlap; the forests and the fauna are mixed, and northern and southern trees and animals grow and live side by side. In this zone we enter the true agricultural part of our country, and the hardier crop plants attain their highest perfection. In the Carolinian zone trees adapted to a warmer climate, like the sassafras and tulip tree, first make their appearance, and the semi-hardy fruits, the sweet potato, tobacco, and the hardier grapes reach their best conditions. In the Austro-riparian zone, the long-leaved pine, magnolia, and live oak are common on the uplands, and the bald cypress and cane in the swamps; the animals and birds are characteristic. This is the zone of the cotton plant, sugar cane, rice, pecan, and peanut, and of tender fruits. Still farther south is the Tropical region, which in the United States is restricted to southern Florida and extreme southeast Texas, along the Rio Grande and the Gulf coast. The Division of Ornithology and Mammalogy is engaged in tracing the courses of these regions across the continent, and in the preparation of large scale maps on which their boundaries are shown in different colors.

Antillean Elevations and Depressions.—A study by Charles Torres Simpson, on the distribution of the land and fresh-water mollusks of the West Indian region, touches upon the evidence they afford with regard to past changes of land and sea. The author finds that a considerable proportion of the land snail fauna of the Greater Antilles seems to be ancient and to have developed on the islands where it is now found. There appears to be good evidence of a general elevation of that region after most of the more important groups of snails had come into existence, at which time the larger islands were united and a land connection existed with Central America by way of Jamaica, and a considerable exchange of species went on between the two regions. At some time during this elevation there was probably a landway from Cuba across the Bahama plateau to the Floridian area, over which certain groups of Antillean mollusks crossed. This period was followed by one of general subsidence, during which Jamaica was first isolated, then Cuba, and afterward Hayti and Porto Rico. The connection between the Antilles and the mainland was broken, and the Bahama region, if it had been previously elevated above the sea, was submerged; the subsidence continuing until only the summits of the mountains of the Greater Antillean islands remained above water. Then followed another period of elevation, which has lasted, no doubt, until the present time, and the large areas of limestone uncovered in the Greater Antilles furnished an admirable field for the development of the groups of land snails that survived on the summits of the islands. The Bahamas have appeared above the surface of the sea, either by elevation or growth, and have been peopled by faunas drifted from Cuba and Hayti, and a number of land and fresh-water species have been colonized in south Florida. The Lesser Antilles have been peopled for the most part from South America.

Smoking in Mashonaland.—The luxuries indulged in by the Mashonas appear, according to W. A. Eckenberg, of the railroad survey, "to be confined to tobacco—not usually smoked, but taken as snuff—and beer manufactured from the seed of the millet. Drunkenness is an uncommon vice, except among certain of the chiefs. In the coast districts hemp is smoked in a hookah pipe of simple construction. A long, narrow gourd forms the body of the pipe. Halfway down it a hole is made of a convenient size for applying the lips. The gourd is filled with water halfway to the level of the hole. Through the closed top is inserted a small hollow reed, reaching nearly to the bottom of the water, and protruding well beyond the upper end of the gourd. To the upper end of the reed is fixed the clay or stone bowl of the pipe, and this is of very small size, capable of holding only a sufficient quantity of hemp for a few whiffs. The smoker, holding the gourd upright to prevent the escape of the water, applies his lips to the hole, and draws the smoke to his lungs, through the water, by two or three vigorous inhalations. The result is made known to the whole neighborhood by a violent and apparently purposely exaggerated coughing and spluttering; the