Contents 



Progressive Fixation of Characters 340 

 Developmental Interactions in 

 Later Stages 341 



Hormones in Growth and Differ- 

 entiation 342 



SECTION VII 

 SPECIAL VERTEBRATE ORGANOGENESIS 



Chapter 1. Nervous System (Neurogenesis) 



BY PAUL WEISS 



346 

 346 



The Object and the Problems 346 



Analysis of the Development of a 



Neuron 350 



Development of the Central Nerv- 

 ous System (CNS) 370 



Development of Behavior 390 



Conclusions 392 



Chapter 2. Eye 



BY VICTOR TWITTY 



Determination of the Retina .... 402 



Induction of the Lens 404 



Induction of the Cornea 407 



Growth of the Eye and its Associ- 

 ated Structures 407 



Regeneration of the Eye 409 



402 



Chapter 3. Ear and Nose 415 



BY c. L. yntema 



Localization of Rudiments 415 



The Ear 415 



The Nose 423 



Problems 424 



Chapter 4. Limb and Girdle 



BY J. S. NICHOLAS 



Vertebrate Appendages 429 



The Development of the Forelimb 

 in Amblystoma 429 



Basic Experimental Work on the 



Limb 431 



The Girdle 434 



429 



Chapter 5. Heart, Blood Vessels, Blood, and Entodermal Derivatives 440 



BY W. M. COPENHAVER 



Heart and Blood Vessels 440 Entodermal Derivatives 453 



Blood 452 



Chaper 6. Urogenital System 



BY R. K. BURNS 



The Nephric System 462 The Genital System 470 



462 



Chapter 7. Teeth 



BY IS.\AC SCHOUR 

 Introduction 492 



492 



Growth 492 



