CONTENTS XV 



Page 

 CHAPTER LV 



Class Amphibia 304 



Classification — Urodela — Salieutia — A pod a — F o o d — C o 1 o r changes in 

 amphibia — Nervous system and sense organs — Behavior — Reproduction 

 and development — Neoteny and pedogenesis — Regeneration — Hibernation 

 — Economic importance. 



CHAPTER LVI 



Reptiles and Birds 375 



Structural characteristics — Embryonic modifications — Egg — Amnion — 

 Allantois — Body coverings. 



CHAPTER LVII 



Class Reptilia 379 



Classification — Internal structure— Squamata — Chameleons — Lizards — 

 Snakes — Venomous snakes — Rhynchocephalia — Crocodilia — Testudinata — 

 Economic importance. 



CHAPTER LVIII 



Class Ayes 390 



External characteristics — Feathers — Internal structure — Classification — 

 Origin of birds and of flight — Flight — The bird as a flying animal — Modifica- 

 tions of l)irds — Plumage — Songs — Migration of birds — Reproduction — 

 Economic importance. 



CHAPTER LIX 



Class Mammalia 406 



External characteristics — Hair — Internal structure — Classification — Origin 

 of mammals — Monotremes — Marsupials — Unguiculata — Primates — 

 Ungulata — Cetacea — Hibernation — Reproduction — Economic importance. 



CHAPTER LX 



Anthropoid Apes and Man 422 



Manlike apes — Erect position — Evidences in man of former arboreal life — 

 Intermediate forms — Fossil men — Present-day man. 



PART V 



General Considerations 



CHAPTER LXI 



Animal Organisms 429 



The organism — Definition — Income and outgo — Differentiation — Integra- 

 tion — Centralization — Chemical control — Individuality — Life cycle in birds 

 and mammals — Other life cycles — Practical considerations — Organismal 

 concept. 



CHAPTER LXII 



Structure of Organisms 435 



Grades of organization — Germ layers and tissues — Relationship of cells in 

 metazoans — Organs and systems — Tegumentary system — Skeletal system — 

 Digestive system — Glands — Respiratory system — Circulatory system — 



