PREFACE. ix 



they have bestowed on what, in my judgment, is one of the 

 most important parts of the book. 



I shall be very grateful for corrections or suggestions from 

 those who use the book. I would further venture to make 

 an earnest appeal for assistance to those who have opportunity 

 of obtaining human embryos, and who do not require them for 

 their own purposes. Our knowledge of the early stages of 

 development of the human embryo is still very imperfect, and 

 it is of the utmost importance that any opportunities that may 

 occur of extending it should not be lost. Embryos of any age, 

 but more particularly those of the first month or six weeks, 

 would be of the greatest service to myself : they should be put 

 into strong spirit as quickly as possible, a little cotton-wool 

 being placed in the bottle to support the embryos, and to pre- 

 vent them from shaking about, during transit ; and any facts, 

 such as the date of the last occuri'ing menstruation, which would 

 aid in determining the age, should be carefully recorded. 



A. M. M. 



OWEKS COLLEGE : March 1893. 



