vi COMPARATIVE ANATOMY 



enable an ordinarily intelligent reader to obtain a clear grasp of the 

 facts and of their relation to one another; a knowledge of the 

 technical terms is of secondary importance, and is easily acquired. 



We trust that this translation of the work of our friend and (in 

 the case of one of us) former teacher, Professor Lang, will prove as 

 useful to earnest students of biology in the English-speaking world 

 as it has proved to ourselves. 



H. & M. B. 



JENA, 1891. 



