THE HYPOPHYSIS IN REPTILES 



231 



thelium. On either side of Rathke's pouch are smaller evagina- 

 tions, long cranio-caudal ridges — the lateral buds — separated 

 from the pouch by distinct furrows. The opening to the out- 

 pouching is wide (fig. 14), the lumina of the three evaginations 

 forming a common hypophyseal cavity. The carotid arteries 

 lie on either side of the hypophysis, near the lateral lobes. On 

 either side, also, are veins with anastomosing branches, one 



Figs. 14 to 17 Median sagittal sections of the hypophyses of lizard embryos. 

 X 40 (M. U. E. C. 565, 576, 563, 564 Lacerta agilis). 14, 5 mm.; 15, 9 mm.; 16, 

 11.6 mm.; 17, 15 mm. (greatest length of coil). A, anterior lobe; /, pars inter- 

 media; R, Rathke's pouch; B, section of brain wall; C, cartilage; M, epithelium 

 of mouth; N, notochord; v, veins. 



lying caudal to Rathke's pouch, the other just anterior, in the 

 angle formed by the cranial wall of Rathke's pouch and the 

 anterior thickened arm of epithelium. As Gaupp ('93) has 

 stated, a venous channel thus surrounds Rathke's pouch. 

 Caudal to the pouch, the roof of the pharynx forms a slight 

 angle, Seessel's pouch, less prominent than in the 3 mm. embryo. 

 The notochord comes into contact with the epithelium of this 

 angle. 



