CONTENTS V 



PAGE 



Functions of the Four Main Parts of the Neurocranium 434 



Adjustments of the Neurocranium to Various Types of Jaws, Different Positions of Mouth, etc. 438 



Responses to Cranial Diverticula of the Swim-bladder 439 



Moulding Influence of the Eyes * 439 



Influence of the Auditory Capsules 440 



Adjustments in the Ethmoid Region 440 



Effects of Special Accessory Organs (Trigger, Illicium, etc.) 440 



Adjustments to Different Types of Skin .441 



Spinescence 441 



Development of a Cranial Buckler ... 441 



Adjustments for Balance and Flotation 441 



Why the Fish Skull Is Divided into Separate Bones 442 



Discussion: The Fish Skull AS A Document OF Evolution 443 



Development and Evolution 443 



The Mechanism of Regulation 444 



The Paradoxes of Adaptation 446 



"Basic Patents" and Evolution 448 



Fish Skulls and Natural Selection 448 



Summary: The Problem of Differential Growth and Evolution in Fish Skulls. . . 450 



The Role of Development 450 



The Three Main Skull Types: Long, High, Broad 450 



Correlation of Skull-form and Body-form 450 



The Interaction of Growing Parts .... 453 



Evolution through Differential Growth Rates 453 



The Mechanism of Correlation 454 



Bibliography 457 



Index 469 



