THE HYPOPHYSIS IN REPTILES 



235 



pouch. They open caudo-laterally into the anterior bud near 

 the hypophyseal stalk (fig. 68). Rathke's pouch lies against 

 the brain in the region of the undeveloped infundibular evagina- 

 tion (fig. 22). The notochord curves downward and backward 

 and comes into contact with the caudal surface of the pouch. 

 The cerebral carotid arteries lie on either side, caudal to the 

 lateral buds. The floor of the anterior lobe is connected by a 

 wide stalk with the pharyngeal roof. This lobe projects cra- 

 nially, and its caudal end is continuous withlRathke's pouch. 



Figs. 18 to 21 Transverse sections of the hypophysis of an adult Sceloporus 

 X 35 (W. U. C. 188). Fine stipple, anterior lobe; lined, pars intermedia; black, 

 brain and infundibulum; b, basis cranii; Ca, carotids; Mu, muscles; s, rem- 

 nant (?) of stalk. 



Dorsal to the attachments of the lateral buds, are two evagina- 

 tions from the anterior lobe extending toward the brain. Reese 

 figured these evaginations (Reese '10, fig. 4b, o") but did not 

 follow their further development. The evaginations shown by 

 him in figure 4, b, and c,o', correspond to the lateral buds of 

 other reptiles. 



In a 19 mm. embryo Rathke's pouch projects dorsally beyond 

 the tip of the notochord. The lateral buds are elongated. The 

 hypophyseal stalk is attached to the floor of the anterior lobe 

 near its cranial end. The stalk arches caudally where it is con- 

 tinuous with the oral roof (fig. 23). 



