HYPOPHYSIS OF PETROMYZON AND AMIA 



273 



Petromyzon fltiviatilis. Ammocoete. Further exten- 

 sion of the hypophysial cavity and separation from the glands. 



Text-fig. 19. 



Petromyzon planeri. Adult. Longitudinal section show- 

 ing the separation of the glands from the hypophysial cavity and 

 the great extension of the latter. 



