250 E. A. BATJMGARTNER 



an actual shifting of the hypophyseal stalk in alligators is seen 

 in figure 51 where the point of attachment to the oral roof has 

 been taken as a fixed point. 



As described by Gaupp, Bruni and others, in all forms the 

 stalk is attached to the anterior lobe. In older turtle embryos 

 it extends from the ventral surface of the anterior lobe near its 

 caudal end; in lizards from somewhat nearer, the anterior end 

 (described by Bruni in Gongylus); and in snakes and alligators 

 close to the anterior end. 



A long tubule, extending caudally from the ventral surface of 

 the hypophysis in an adult alligator 47.5 cm. in length, as well 

 as one in a 22 cm. embryo extending through the cranium 

 almost to the epithelial lining of one of the nose cavities, is 

 undoubtedly the remnant of the stalk. In these adult speci- 

 mens as well as in late embryos this stalk extends caudalward 

 from near the caudal end of the anterior lobe. 



There is reason for thinking that some of the tubules described 

 in some of the turtles and lizards are also remnants of the stalks. 

 In a young turtle a tubule extends forward from about the 

 middle of the hypophysis. If this be the remnant of the stalk, 

 it may be that the shifting of its attachment has been brought 

 about by the growth of the cranium, or, to a late caudalward 

 shifting of the hypophysis. In an adult Sceloporus a similar 

 cystic tubule extends along the ventral surface of the hypophysis 

 for some distance. It is possible, of course, that occasionally 

 the stalk will persist at least until adult life. This possibility, 

 together with the position and appearance of the tubules make 

 it probable that the structures described are hypophyseal stalks 

 or remnants of stalks, although they may be dilated tubules. 

 There is no evidence in any of the specimens of any proliferation 

 from the pharyngeal end of the stalk forming a pharyngeal 

 hypophysis such as has been described in some mammals. 



Saint Remy ('96) has located the anterior end of the noto- 

 chord in various Amniota. In reptiles he found it attached to 

 the entoderm between Rathke's and Seessel's pouches. He de- 

 scribed ascending and descending limbs of the anterior end of 



