Obstetrics : the science and the art . n-nexed cut, Fig. 43, also copied fromhis lithograph. It is a cross sectionof a portion of the yelk-ball and thecumulus, with its cavity, in the hollowof which was found the Purkinjean vesicle. The transparent vesicle thus revealed is almost as delicatein its structure as a soap bubble. It can be found only in eggsthat have not been fecundated, such as the pullets eg<^ or yelks takenout of the ovary, in which, according to Von Baer, it exists, even inthe very smallest yelks. Fecundation abolishes it. The Student has now a clear understanding as to the
Obstetrics : the science and the art . n-nexed cut, Fig. 43, also copied fromhis lithograph. It is a cross sectionof a portion of the yelk-ball and thecumulus, with its cavity, in the hollowof which was found the Purkinjean vesicle. The transparent vesicle thus revealed is almost as delicatein its structure as a soap bubble. It can be found only in eggsthat have not been fecundated, such as the pullets eg<^ or yelks takenout of the ovary, in which, according to Von Baer, it exists, even inthe very smallest yelks. Fecundation abolishes it. The Student has now a clear understanding as to the germinal orPurkinjean vesicle, discovered and made known in September, Purkinjean vesicle is the germinal vesicle that is found inside ofthe unfecundated yelk, whether of birds or women or other animals. The next publication in the order of important discovery, wasJ) ovi Mammalium et Hbminis 6r< ? •?. A* si • ? < ? Acad nam arum P A. B Zoologia Prof. /??. ord. I: ?. cum Tabula Aenea. Lips. 1827, 124 THE OVARIES. Such is the title of Von Baers letter to the Imperial Academy ofSciences at St. Petersburg, on the subject of the ovum of the mammi-ferous quadrupeds. In Von Baers experiments, he, like Purkinje, never could find thevesicle in eggs already laid, but always detected it in even the smallestyelks of the egg bag. He supposes it to be the nucleus around whichthe matter of the yelk becomes subsequently aggregated. This wasthe case also in the molluscs, in the lumbricus and in the researches led him to the discovery of the mammiferous ovu-lum, in the following manner. Having observed a very minute ovulum in the Fallopian tube ofthe bitch, and reflecting that such small ova could not consist ofGraafian vesicles, which are much larger, and that the liquor of theGraafian vesicle could not so soon acquire the firmness and solidity ofthe tubal specimen, he was led by curiosity, rather than by the hopeof seeing with the naked eye, through the s
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Keywords: ., boo, bookcentury1800, booksubjectmidwifery, booksubjectobstetrics
