TRANSLATOR'S NOTE 



I OFFER THIS English version of De Graaf's famous description of the ovaries, 

 for publication in honor of Herbert McLean Evans, in the hope that it 

 will recall to him the happy days when he and I worked side by side in his 

 laboratory, students of the ovary no less enthusiastic than our predecessor 

 De Graaf. Himself, like De Graaf, a distinguished contributor to the physi- 

 ology as well as the anatomy of the reproductive system, he will (I hope) find 

 pleasure in reading this masterpiece of the brilliant young Dutchman. 



In another place (Corner, 1930) I have discussed the background and the 

 relative importance of the contribution made by De Graaf. It will be suffi- 

 cient to say here that what follows is the first thorough description of the 

 mammalian female gonad and that it proved and established the fact that 

 this organ, like the ovary of birds, is actually an ovary. De Graaf did not, of 

 course, identify the actual ovum; by a very excusable error he assumed that 

 the whole contents of the follicle is the egg. He was, indeed, much surprised 

 when he traced the rabbit's embryos back to the third day after copulation, 

 when they were still blastocysts in the oviduct, to find them so much smaller 

 than the follicle. This discrepancy De Graaf never solved. 



His name has long been attached to the ovarian follicle, but it might with 

 more justice have been applied to the corpus luteum; for the latter receives 

 in this chapter its first good description, whereas the follicles had been seen 

 previously and the description given of them here is not much more extensive 

 than that of his predecessors. 



The chapter has, to the best of my knowledge, been translated into modern 

 languages only twice before. The whole book on the female reproductive 

 system is included in the Dutch translation of the complete works of De 

 Graaf, published at Leyden in 1686. Our chapter on the ovaries was trans- 

 lated into English by that remarkable anatomist of Edinburgh, Robert Knox, 

 in 1848. This version, published in an obscure place, is now scarce. The Army 

 Medical Library kindly permitted me to have it photographed. In polishing 

 my own version I have not hesitated to borrow a happy word from Knox now 

 and then, and in return I believe I have corrected one or two errors in his 

 translation. In doubtful cases I have accepted as probably correct the reading 

 of the Dutch translation, made within a few years of the original Latin text. 



The three plates which accompany the chapter have been photographed 

 from a copy of the first Latin edition in my possession. 



The portrait of De Graaf has been redrawn by Mr. D. K. Winter from the 

 contemporary engraving which was used as the frontispiece of De Mulierum 

 Orga7iis and of the complete Opera. 



[1233 



