. Chemical embryology. Embryology. 674 THE RESPIRATION AND [PT. Ill just as much associated with high respiratory rate as mitotic activity. The question is in a confused and unsatisfactory state, and further researches with more accurate methods are greatly to be desired. Another pioneer worker on the respiration of the amphibian em- bryo was Godlevski, who published his work in 1900 in connection with the susceptibility of frog's eggs to oxygen want. His technique was rather better than Bataillon's. The data he obtained are shown in Fig. 128, and consist of two smoothly ascending lines compos
. Chemical embryology. Embryology. 674 THE RESPIRATION AND [PT. Ill just as much associated with high respiratory rate as mitotic activity. The question is in a confused and unsatisfactory state, and further researches with more accurate methods are greatly to be desired. Another pioneer worker on the respiration of the amphibian em- bryo was Godlevski, who published his work in 1900 in connection with the susceptibility of frog's eggs to oxygen want. His technique was rather better than Bataillon's. The data he obtained are shown in Fig. 128, and consist of two smoothly ascending lines composed of rather scattered points. Nothing further was done on amphibian embryo respiration till 1915, when Bialascewicz & Bledovski attacked the question, using the Winterstein micro-respirometer, a great advance on the technique of the earlier workers. The eggs of Rana temporaria were used. Bialascewicz & Bledovski found that, during the first few hours after laying, unfertilised eggs hberated a "neutral gas" which, as far as could 0-5 be ascertained, was a mix- ture of oxygen and nitro- gen. This doubtless arose from the difference in en- vironment as regards gases between the ovary in the female body and the water outside. One thousand eggs gave rise in this way to a positive pressure of I2'i mm. 16 minutes after laying, and 1-15 mm. 47 minutes after laying, but thenceforward the pressure was constantly a slightly negative quantity. In order to avoid technical errors which arose naturally from this fact, Bialascewicz & Bledovski compensated the gaseous exchange of one lot of eggs in one vessel by having an identical quantity of eggs from the same female in the other vessel. Another phenomenon seen in the unfertilised eggs was a notable production of carbon dioxide immediately upon laying. Eggs taken from the lower part of the oviduct and brought straight into the micro-respirometer eliminated large amounts of carbon dioxide, presumably because
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Keywords: ., bookcentury1900, bookpublishernewyorkthem, booksubjectembryology
