ABSTRACT
The present paper is the result of an attempt to collect together and give an account of the literature of the formation of the corpus luteum, during the last ten years, that is, since the publication of Sobotta’s first paper on the corpus luteum of the mouse.
Vide Sobotta, Merkel and Bonnet’s ‘Ergebnisse d. Anal. u. Entwick.’ vol. xi, 1902.
Schmidt’s paper, besides containing observations on the corpora lutea, has also an interesting account of the variation noted in the duration of the œstrous cycle, or the interval between two successive “heat” periods, in cattle, as deduced from the study of 500 cases. The most usual length of this period appears to be twenty-one days, but the variation was found to range from six days to one hundred and twenty-one, or even more days. All variations between these periods were noted to occur. Schmidt’s observations are in direct opposition to Beard’s speculation regarding the “Span of Gestation and the Cause of Birth” (Jena, 1897), according to which the interval between two “heat” periods is assumed to bear a fixed relation to the length of the gestation period.
