Proceedings of the Academy of Natural Sciences of Philadelphia, 1874 (Classic Reprint)
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Excerpt from Proceedings of the Academy of Natural Sciences of Philadelphia, 1874 A large running along a rafter in his greenhouse, and producing hundreds of flowers, bore these dimorphous ones in about equal proportions. He said it was well known that in cultivation this plant never produced fruit unless by artificial cross-impregnation, but he thought the tendency to abort in the female flowers, and thus approach the classes which were in structure as well as practically uni-sexual, had not been noticed before. There was a species in New Zealand, however, known to be monoecious, and it might be just possible that the Passifloraceæ, with mostly hermaphrodite flowers, were following in the wake of the allied Cucurbitaceæ, in which a complete separation of the sexes was the rule. January 13. The President, Dr. Ruschenberger, in the chair. Twenty-six members present. Remarks on Hydra. - Prof. Leidy remarked that two species of Hydra were common in the neighborhood of Philadelphia. One is of a light brownish hue and is found on the under side of stones and on aquatic plants in the Delaware and Schuylkill rivers, and in ditches communicating with the same. Preserved in an aquarium, after some days the animals will often elongate the tentacula for several inches in length. The green Hydra is found in ponds and springs attached to aquatic plants. It has from six to eight tentacles, which never elongate to the extent they do in the brown Hydra. In winter the animal is frequently observed with the male organs developed just below the head as a mamma-like process on each side of the body. He had not been able to satisfy himself that these Hydræ were different from H. fusca and H. viridis of Europe. Prof. Agassiz had indicated similar colored forms in Massachusetts and Connecticut, under the names of H. carnea and H. gracilis. Of the former he remarks that it has very short tentacles, and if this is correct under all circumstances, it must be different from our brown Hydra, which can elongate its arms for three inches or more. January 20. The President, Dr. Ruschenberger, in the chair. Thirty members present. Prof. E. D. Cope described some species of extinct tortoises from certain formations of Northeastern Colorado, which had been previously found in the Fort Union or lignite beds of the Missouri river region by Dr. Hayden. 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.
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