No fact has more profoundly puzzled the vegetable physiologist than the alternations of forest growths which are everywhere occurring without the apparent interposition of natural seeds, and which have been considered as wholly inexplicable except as one unsatisfactory theory after another has been suggested to account for the wide dissemination and distribution of their seeds. We have had any number of these theories, more or less ingeniously constructed, but it is safe to say that none of them satisfactorily accounts for more than a very limited number of the phenomena presented. It is only within a comparatively recent period that these alternations of timber growth have attracted the attention of scientific men; consequently little more than crude suggestions and ill-digested facts are at the command of the general reader and writer. And yet the facts themselves, such as they are, would fill a dozen volumes of the size of Dr. Hough's recent "Report upon American Forestry." We can only give a few of the more important facts we have gathered, and many of these are so deficient in necessary detail that their value is greatly lessened for scientific uses. This is especially true of nearly all those noticed and collated by Dr. Hough, in his report to the United States Commissioner of Agriculture, made in 1877, in which the alternations in question are referred to at length, but no new suggestions presented, nor any very important new facts given. If our construction of the Bible genesis be the correct one, it will, we think, be unhesitatingly admitted that all the facts collected and collated by Dr. Hough, together with others more carefully noticed by our ablest writers on vegetable physiology, not only harmonize with this ancient Hebrew text, but so completely fit into it, both in its implications and explications, that adverse criticism will be awed into silence rather than provoked into any new controversy on the subject. This remarkable genesis declares that the germs of all living things are in themselves upon the earth--"upon the face of all the earth." It is true that this declaration, as contained in the 11th verse of the first chapter of Genesis, is textually limited to the vegetation of the earth; but the further emphatic statement that "the animating principle of life" is in the earth, coupled with the more substantive fact that God commanded the waters and the earth to bring forth abundantly of every living creature, with the single exception of man, conclusively extends the language of the 11th verse to whatever vegetable and animal life the earth was specifically directed to "bring forth." It is our purpose to consider, in this connection, not only the various facts noticed and theories suggested by our ablest writers and thinkers on the subject of seed-distribution, but to ascertain, as far as possible, to what extent their several facts and theories harmonize with natural phenomena, and at the same time