The Journal of 



Comparative Neurology and Psychology 



Volume XIX November, 1909 Number 5 



THE MORPHOLOGY OF THE EOREBEAIN" VESICLE 

 IN VERTEBEATES.i 



BY 



J. B. JOHNSTON. 



University of Minnesota. 



With Fobty-five Figures. 

 CONTENTS. 



PAGE 



Introduction 458 



T. Descriptive part _ . . 462 



1. Cyclostoiues 462 



2. Selachians 464 



Notes on bead morplaology 464 



Development of the forebrain 479 



a. The optic vesicle and the primitive optic groove 479 



b. The floor of the diencephalon 482 



c. Roof of the diencephalon 487 



3. Ganoids and teleosts 488 



4. Amphibians 489 



5. Reptiles and birds 495 



6. Mammals 495 



^Neurological studies from the Institute of Anatomy, University of Minne- 

 sota, No. 6. 



The Journal op Comparative Neurologt and Psychology. — Vol. XIX, No. 5. 



