X CONTENTS 



PART IV 



HUMAN STRUCTURE AND PHYSIOLOGY 

 (Chapters XXI-XXVIII by Isabel McCracken) 



CHAPTER PAGE 



XXI. Introduction, and the Chemistry of Physiology 287 



XXII. Digestion and Absorption . 303 



XXIII. The Blood and Circulation 316 



XXIV. The Skeleton and Muscles 329 

 XXV. Respiration and Excretion 343 



XXVI. Nervous System 357 



XXVII. The Special Senses . . 368 



XXVIII. Micro-organisms and Sanitation 379 



XXIX. Ancient and Modern Man 384 



PART V 



ANIMALS IN RELATION TO EACH OTHER, TO PLANTS, AND 

 TO THE OUTSIDE WORLD 



XXX. The Struggle to Live, Adaptation, Distribution, Etc. 399 



XXXI. Parasitism and Degeneration . 411 



XXXII. Mutual Aid and Communal Life . 421 



XXXIII. The Colors and Markings of Animals, and Their Uses 438 



XXXIV. Insects and Flowers . 450 



APPENDICES 



1. Student and Classroom Equipment and Methods . 467 



2. Rearing Animals and Making Collections 469 



Index . . 483 



