PREFACE 



Atwell (Fig. 2), Dr. H. H. Cole (Fig. 42), Professor E. T. 

 Engle (Fig. 36), Professor H. M. Evans (Figs. 25-27), Dr. 

 M. S. Gilbert (Fig. i), Professor C. M. Gruber (Fig. 54), 

 Professor Leo Loeb (Fig. 49), Professor C. R. Moore (Fig. 

 37), Dr. A. S. Parkes (Figs. 23 ^^^ 40> Professor A. T. 

 Rasmussen (Fig. 6), Professor P. E. Smith (Figs. 24, 38, 39, 

 and 45), and Dr. J. M. Wolfe (Fig. 10 and data of Table IV). 

 I wish also gratefully to acknowledge the permission of 

 the Anatomical Society of Great Britain and Ireland to re- 

 produce Figure 4, which was first published in the Journal of 

 Anatomy. To the Verlagsbuchhandlung Julius Springer, I 

 am under obhgation for permission to use Figures 5, 40, 

 43, and 44. The University of Cahfornia Press kindly con- 

 sented to my use of Figure 27. Finally, I wish to express my 

 thanks to editors or publishers who permitted me to repro- 

 duce illustrations or data from the following journals: the 

 American Journal of Anatomy^ the American Journal of 

 Physiology., the Anatomical Record., Endocrinology., the Jour- 

 nal of Biological Chemistry., the Journal of Pharmacology and 

 Experimental Therapeutics^ and the Journal of Physiology. 



H. B. VAN Dyke 



Peiping Union Medical College 

 1936 



