Contributions to the Natural History of the Acalephae of North America (Classic Reprint)

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Excerpt from Contributions to the Natural History of the Acalephae of North AmericaThe study of such animals is therefore of high physiological importance, as it will enlarge our views of animal functions, and give more precision to our ideas of cellular life, and the more so, because in this, as well as in several other naked - eyed Medusa, we can satisfy ourselves with the greatest ease, that the different organs which per form here different functions are entirely and exclusively composed of cells, not in the same sense as it can be said of the body Of higher organisms, but strictly so, the cells here not undergoing any extensive metamorphosis by which they are transformed into distinct tissues of different structures, though derived from cells. Here they preserve the appearance of indisputable cells, combined in various ways, slightly modified in differ ent parts Of the body, but everywhere to be recognized as cells although performing the most heterogeneous functions. Here a heap of large cells, containing a crystal-like, more consistent ¿uid, constitutes the main mass of the body. Other series of somewhat elongated, more or less bottle-shaped, contractile cells, elongating and shortening alternate ly, constitute bundles or layers Of an apparently fibrous tissue, which is, however, only an accumulation of slightly modified cells representing the muscular system, and acting as such with as much energy as the striated muscles, though here we have no muscular bundles proper, no primitive fibres whatever, no striation upon the contractile tissue, but cells, the walls of which are contractile and act as muscles. (plate V., the parts in blue.)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.