. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 222 A. M. REESE. The outline of the inner envelope is sharp and even, while that of the outer envelope (Fig. I, o. e.) is more or less irregular and uneven. The outer envelope is composed of such trans- parent jelly that it might easily be overlooked at the first glance. It forms a continuous layer over the entire mass of eggs. When the unfertilized eggs are left for some days in water, they become very much swollen, by the osmosis of water through the vitelline membrane, and may eventually burst. There was no apparent swell
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 222 A. M. REESE. The outline of the inner envelope is sharp and even, while that of the outer envelope (Fig. I, o. e.) is more or less irregular and uneven. The outer envelope is composed of such trans- parent jelly that it might easily be overlooked at the first glance. It forms a continuous layer over the entire mass of eggs. When the unfertilized eggs are left for some days in water, they become very much swollen, by the osmosis of water through the vitelline membrane, and may eventually burst. There was no apparent swelling of the gelatinous envelopes on coming in contact with water as is de- scribed in connection with some other amphibian eggs. Several dozen eggs were obtained from one average-sized female, about two dozen being^drawn, without appar- ent injury, from the cloaca, while the rest were obtained only after killing the animal and opening the body cavity. All the eggs obtained in the latter way were found to be contained in the right oviduct, the ova of the left ovary being nearly all in a very immature condition. Whether or not this was a normal condition, indicating perhaps, a very prolonged breeding season, it was not possible to say. The spermatozoa were obtained as a milky fluid from the living males by the usual process of stripping, though considerable pressure had, in most cases, to be exerted. They were immediately examined under the higher powers of the microscope, but no motion could be detected, though it would naturally be expected that spermatozoa obtained in this way would show the usual activity of mature spermatozoa. An attempt was made to artificially fertilize the eggs by put- ting them into a dish of water into which a great number of spermatozoa had been stirred, but the attempt was entirely un- FIG. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appeara
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
