PREFACE 



THIS book has a twofold purpose: first, to present the re- 

 sults of modern anatomical and embryological research rela- 

 tive to the human structure in a form accessible to the general 

 student, and, secondly, to furnish students of technical human 

 anatomy with a basis upon which to rest their knowledge of 

 details. 



Regarding the first of these purposes, it may be said that, 

 while many of the phases of the doctrine of evolution have 

 been thoroughly exploited, and their general teaching has be- 

 come the property of the general scholar, the contribution 

 to thought furnished by anatomy has been considered of too 

 technical a character for popular presentation. It is true that 

 this science necessarily rests upon a material basis, and in- 

 volves a mass of extremely intricate details, and it is also true 

 that a more or less complete knowledge of these is absolutely 

 necessary before the contribution of this science to evolution- 

 ary thought can be appreciated ; but in these respects anatomy 

 does not differ from other branches of natural science, the 

 essential teachings of which are already a matter of general 

 knowledge. If, then, the technical difficulties have been sur- 

 mounted in the case of Geology, Astronomy and general 

 Zoology, it is not too much to hope that in the course of the 

 next few years the mission of Anatomy may also become gen- 

 erally known, especially since its results touch human interests 

 more closely than do those of any of the kindred sciences. 



Concerning the second purpose, that of assisting in the 

 technical study of 'human anatomy, it is hardly necessary to 

 present an argument, since the great advantages of studying 

 human anatomy in connection with both comparative anatomy 

 and embryology are patent to all who have employed this 

 method. While there are still a few human anatomists who 

 present the old argument that the science is too full of detail 

 already to allow the assumption of additional facts, the ex- 



