Page:The Harveian oration delivered at the Royal College of Physicians June 26, 1872 - being an analysis of Harvey's Exercises on Generation (IA b2231295x).pdf/12

3 In order that we may the better understand Harvey's position when he commenced those studies of which the ultimate fruit was his cele- brated treatise on Generation-it is desirable to bear in mind the prevalent physiological doctrines of that day. Harvey found the teachers of this branch of physiology divided into two. principal parties. According to the teaching of Aristotle, the principles of generation were the male and the female, she contributing the matter, he the form; and immediately after conception the vital principle, and the first particle of the future foetus-namely, the heart, in animals having red blood-were formed from the menstrual blood in the uterus. On the other hand, the followers of Galen, with whom were the physicians, taught that the semen of both parents combined fur- nished the offspring, which resembled one or other according as this or that predominated, and that by virtue of such predominance it became either male or female. Neither of these doctrines, however, gave satis- faction to Harvey, but the contrary. "That they are erroneous and hasty conclusions,' he says, 'is easily made to appear: like phantoms of darkness,