SECT. 2] TO THE RENAISSANCE 115 



out from the spongy substance of the uterus and this blood growing 

 in bulk forms a soft and fungus-like mass of flesh, rather like the 

 substance of the spleen, which adheres to the surface of the uterus 

 and transmits to the foetus in proportion as it grows the nourishment 

 for it which reaches the uterus in the form of blood and spirits". 

 Then, going on to discuss the functions of the jecor uterinae, as 

 he calls the placenta (with what justice may be seen by turning to 

 Section 8-5), he devotes a chapter to De vasorum umbilicalium origine, 

 and, contradicting Hippocrates, Galen, Erasistratus, and Aetius, says 

 that the maternal and foetal blood-vessels do not pass into each 

 other by a free passage. "This is repugnant to sense", he writes, 

 "and as may be seen by ocular inspection, these vessels do not reach 

 the inner membrane of the uterus, for the substance of the placenta 

 is placed between their ramifications and the proper substance of 

 the womb." He was thus the first to maintain that the maternal 

 and foetal circulations are separate, but he naturally did not, and 

 could not, speak of circulations, since he lived before Harvey. Nor 

 could he have satisfactorily proved his point with the means then 

 at his command, and, as we shall see, it was to take another century 

 before the proof was given. Apart from this valuable contribution 

 to embryology, Arantius gave some admirable anatomical descrip- 

 tions of the foetal membranes. 



Hieronymus Fabricius ab Aquapendente, the pupil of Fallopius, 

 has always been given an important place in the history of embryo- 

 logy by those who have written on him. As one comes upon him 

 in the process of tracing out that history itself, however, he does 

 not take such a high place. With the statement, for instance, that 

 "Fabricius carried embryology far beyond where Goiter had left 

 it and elevated it at one bound into an independent science" I 

 find that I cannot agree. Embryologists who called themselves 

 that and nothing else did not appear till the end of the eighteenth 

 century, and it seems to me doubtful whether the anatomical ad- 

 vances in embryology made by Fabricius are not counterbalanced 

 by the erroneous theories which he invented at the same time. His 

 De Formatione Ovi et Pulli pennatorum, and his De Formato Foetu of 1604 

 show far more scholasticism and mere argumentativeness than is to 

 be found in Goiter, and are remarkable for their bulk. Fabricius 

 seems to have had a genius for exsuccous and formal discussions. He 

 spends much time, for example, in taking up the problem of whether 



8-2 



