THE MORPHOLOGY OF THE FOREBRAIN IN AMPHIBIA 



AND REPTILIA 



C. JUDSON HERRICK 



From the Anatomical Laboratory of the University of Chicago 



EIGHTY-FOUR FIGURES 



Introduction 413 



Amphibia 415 



Urodela 416 



Amblystoma 416 



Othei Urodela 435 



Anura 438 



Comparisons with fishes 449 



Reptilia 452 



Discussion 466 



Diencephalon and telencephalon 466 



The paraterminal body , 483 



The morphology of the cerebral cortex 486 



The subdivision of the prosencephalon 492 



Summary 498 



INTRODUCTION 



Notwithstanding the publication of a great mass of descriptive 

 detail regarding the structure and morphology of the forebrains of 

 lower vertebrates, it is very difficult to form a clear picture of the 

 fundamental morphological features of the vertebrate cerebral 

 hemisphere. This wealth of observation has stubbornly resisted 

 correlation and the morphological fruits of these arduous labors 

 have until very recently, it must be confessed, been disappoint- 

 ingly meager. We have, however, now reached a point where 

 effective correlation has begun to take form and within the be- 

 wildering complexity of detail characteristic of individual species, 

 it is possible to see a common morphological pattern which is sur- 



THE JOURNAL OF COMPARATIVE NEUROLOGY AND PSYCHOLOGY, VOL. 20, NO. 5. 



