VI 



PREFACE 



perience of everyone who has learned the parts of some com- 

 plicated organ like the brain, by the old method, and has had 

 it later elucidated by the new, is a sufficient refutation of 

 such a position. It takes but a little experience with anatomy, 

 as taught by the modern comparative method, to see that this 

 latter furnishes a rational basis for an absolute knowledge of 

 the fundamental relationships, while the old method is largely 

 an intricate system of mnemonics. A student of the older anat- 

 omy must needs remember arbitrarily that two given parts 

 are related in a certain way and not in the reverse way, and 

 if his memory is inadequate to the task he has nothing to 

 save him, while a student, furnished with a morphological 

 basis for his knowledge and able to refer the parts back to 

 a time in which they were in a much simpler condition, will 

 know that they must be related in a certain definite way, and 

 cannot be otherwise arranged. 



The present work has especially the needs of the medical 

 student in mind, since it is not a general comparative anatomy, 

 but, as its title signifies, a " history of the human body," in 

 which the structure of the lower vertebrates is expounded 

 only so far as is needed to throw light upon the relations 

 found in Man. Thus the lines that do not lead in this direc- 

 tion, but represent specialized side-branches, like those of 

 birds or snakes, are barely touched upon, other than as illus- 

 trations of principles similar to those under consideration, 

 although certain exceptional modes of development or eccen- 

 tric specializations are often mentioned on account of their 

 general interest. 



The technical terms of human anatomy employed in this 

 work conform in general to the list prepared by the Basle 

 Anatomical Nomenclature (BNA), but in cases where these 

 terms differ widely from those in common use in America the 

 latter are placed in brackets after the BNA term. In cases 

 where the BNA nomenclature is not in accord with morpho- 

 logical principles, these terms are rejected, but are indicated 

 in brackets or otherwise. Of these, the most important are 

 the following: 



