THE POPULAR SCIENCE MONTHLY.
vests of introduced plants. To show their number, witness the long lists given by Mr. Isaac Martindale of those found near Philadelphia, and of Mr. Charles Mohr, of Alabama, of those found at Pensacola, New Orleans, and other places. Wars, too, are the means of spreading plants. It is said that great numbers of new plants have been found in France, in the vicinity of places where the Germans had brought forage for their horses and stacked it. Of course, many plants introduced in this way do not thrive longer than a year or two, but some of them no doubt take up their residence permanently. Man's propensity to seek out attractive plants in far off countries, and to transplant them to his home to make his garden attractive, has been the means of the naturalization of many species. These have ample opportunity to escape into the surrounding country, and with favorable conditions to spread extensively in all directions. Seeds of many weeds are mixed with the wheat and other grains which man carries with him wherever he goes, and plants wherever he may happen to settle. Railroads are efficient agents in the work. Seeds are lodged on the platforms of the cars, are carried along by the wind created by the passing trains, and in many other ways are distributed along the track. There is an instance of the work of the railroad in the east end of Cincinnati, near Fulton, on the Little Miami Railroad. For the last two or three years there have been growing great numbers of Euphorbia marginata, a plant which is a native of the plains of Kansas, and which is slowly but surely working its way toward the East by means of the railroads. Eastern plants, which a number of years ago were wanted in exchange with the West, are now naturalized in the West, and vice versa.
|HYSTERIA AND DEMONISM.|
A STUDY IN MORBID PSYCHOLOGY.
THE mysterious problem of somnambulism is closely connected with the study of the demoniac affection. It is necessary to enter into some details on this subject, for we should not be able to comprehend the nature of certain epidemics of the middle ages if we were not acquainted with the different symptoms of the sleep called magnetic. Moreover, the effrontery of charlatans has mixed up so many absurdities with the real facts appertaining to this malady that it is hard for persons who have not made a special study of it to preserve a just mean between the credulity that admits
- Translated from the "Revue des Deux Mondes" by W. H. Larrabee.