The Pines of Mexico (Classic Reprint)

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Excerpt from The Pines of Mexico For several years Mr. E. W. Nelson, of the U. S. Department of Agriculture, in connection with his biological explorations in Mexico, has collected specimens of the Pines of that country. The very valuable material that he has brought together was gathered from various latitudes and altitudes throughout Mexico and in parts of Guatemala and in localities remote from the usual lines of travel. His collection, supplemented by that of his associate, Mr. E. A. Goldman and by that of Dr. J .N. Rose of the National Museum at Washington, and his assistants was sent to me for identification and has formed the basis of this paper. In order to study the trees as they grow naturally I have made four journeys to Mexico in company with Mr. C .G. Pringle of the University of Vermont. A cursory examination of the specimens of Mexican Pines preserved in herbaria suggests a large number of species, the varied altitudes and climates of Mexico point to a like conclusion. Each excursion among the living trees, however, increased my suspicion that the numerous forms represent not many species, but several varieties of a few species. It was not until this suspicion became conviction that a consistent systematic arrangement of the Mexican Pines seemed possible to me. Two characters of Pinus may require explanation, 1. - The conelet, or cone of the first year may be subterminal, lateral or pseudo-lateral on the branchlet. When the spring-shoot consists of one internode only the conelet is necessarily subterminal, when the spring-shoot consists of two or more internodes, the conelet may be subterminal or lateral or both. When a conelet is subterminal on the spring-shoot and a summer-shoot grows beyond it, the conelet becomes pseudo-lateral. A pseudo-lateral conelet is easily recognized as the leaves of the summer-shoot never attain normal length [Shaw, Bot. Gas. XLIII, 205.] 2. - At the end of the growing season, buds enclosing staminate flowers are not sufficiently advanced in the Soft Pines to be recognized, but in the Hard Pines they are usually easily distinguished by their large size. The young male aments may either be concealed in the general outline of the bud, in which case they can be found by removing the basal perulae, or they form about the nodes of the bud characteristic enlargements which are constant for each species. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.