The Botanical Gazette, Vol. 71

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Excerpt from The Botanical Gazette, Vol. 71: January-June 1921Nearly a decade ago eames in a publication from this labora tory, made a comparative study of the herbaceous type, which was particularly focussed on the Rosaceae, since this group presents in relative abundance closely related forms of woody and herbaceous texture. This investigator concluded that there is clear evidence in the Rosaceae for the origin of herbaceous stems from woody, as a consequence of the formation of large storage rays in relation to the incoming foliar traces. These rays usually extend some distance below the foliar trace, and also may be developed above it. In the horizontal aspect of the axis, in the region of the node of stems with a well developed fibrovascular cylinder, the storage parenchyma related to the leaf traces can be seen subtending them externally. The development of these masses of storage tissues in woody stems and in correlation to the vascular supply of the leaves (since the masses in question not only subtend the foliar traces vertically but, in cylinders of any thickness, likewise in the radial dimension as well) automatically results in the transformation of the continu ous dicotyledonous woody cylinder (ultimately at any rate) into a circular series of discontinuous fibrovascular segments, the fibro vascular bundles so characteristic of herbaceous stems. Aecom panying the development of the large foliar rays, as pointed out by Ems, is the final degeneracy of the rays of moderate size, which are normally characteristic of the woody cylinder of arboreal Angiosperms.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis 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.