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E. A. BAUMGARTNER 



wide at the apex, circular in the constricted portion, and again 

 widening at the oral end where it receives the openings of the 

 two lateral buds. The lumina of the three outpouchings appear 

 as branches of a common hypophyseal cavity. The oral epi- 



Figs. 1 to 5 Median sagittal sections of the hypophysis of turtle embryos : 

 J 4.6 mm.; 2, 6.4 mm.; 3, 9.2 mm.; 4, 14.5 mm.; 5, 21 mm. Figure 3 is from 

 Chrysemys marginata, others from Aromochelys odorata. X 40 (W. U. C. 79, 77, 

 91, 97, 46). A, anterior lobe; I, pars intermedia; L, lateral lobes; b, basis cranii; 

 B, brain wall; c, anastomosing branch of carotids; C, cartilage; i, infundibulum; 

 M, epithelium of mouth and stalk of hypophysis; N, notochord; R, Rathke's 

 pouch; v, veins. 



thelium, directly anterior to these three outpouchings, is thick- 

 ened and slightly evaginated, forming the anlage of the anterior 

 bud. 



In a 6.2 mm. embryo, the furrows separating Rathke's pouch 

 and the lateral lobes are very wide. The oral epithelium rostral 



