Last night Mr. George James Peirce, of the Scientific School, delivered a Bowdoin Prize Dissertation. His essay was one which would prove especially interesting to students of Natural History, and although it contained many technical terms, it was clearly and concisely written.

All plants are distributed in one of two ways, either by inherent or by extraneous means. The first, perhaps, is the simpler and more natural, and yet it is a well-established fact that as much is done towards reproduction by extraneous means as by inherent ones.

Diagrams were shown by Mr. Peirce by which the formation and organic growth of plants were illustrated. It was shown how fruits and flowers ripen, and how much of their dissemination depends on the shape of the pods of the plants.

The inherent means for the distribution of plants were divided into three classes-by stem, by root, and by fruit-and these were still further subdivided-stem into suckers, runners and rhizomes; roots into aerial growth as is the case with the banyan and rattan; and fruit into dehiscence, both active and passive, and elasticity. Dehiscence is not necessarily elastic, and an ordinary observer cannot fail to corroborate the truth of this statement by seeing the workings of nature in regard to plant growth. Inherent means for dissemination, however, must always prove limited, and it is necessary to depend largely for the distribution of seeds over the world and their growth, upon extraneous means. These are divided into two classes-inorganic and organic. The primary inorganic causes are the actions of winds, streams, currents, and glaciers. It is almost impossible to estimate the amount of work due to these causes, for every one of these inorganic means is almost constantly at work, Organic means are of those of insects, fishes, lower mammalia and man. The buoyancy of seeds differs greatly, and to the greater lightness of some seeds in a great measure is due their greater chances for dissemination; for if they are buoyant they will often be carried a great ways on the surface of the water, and take root in a soil far distant from the place of the original plant from which the ysprung.