THE HOMOLOGY OF MENSTRUATION

Abstract

In these animals as in our own species, the phenomena of conception are brought about in a manner so mysterious that they furnish a vast field for the most diverse interpretations, the most extraordinary conjectures.¹ In November, 1928, I² reported the finding, in a significant number of females of Macacus rhesus, of a slight bleeding at about the midinterval of the menstrual cycle. Reasons were given for concluding that the red blood cells recoverable, usually in microscopic traces, arose from the minute hemorrhage incident to ovulation; that is, the bleeding was interpreted as ovarian in origin. Two observations by laparotomy constituted the chief basis for this conclusion: in one case, in which red blood cells were not found in the vaginal lavage, ovulation had not taken place; in the other, on the contrary, a ruptured follicle was found in correlation with the observed bleeding. Twentythree additional laparotomies, performed