238 



E. A. BAUMGARTNER 



Adult alligators of 22.5 cm. to 150 cm. in length were studied. 

 One of these, cut sagittally, shows clearly the parts with which 

 we have to deal in the adult form. The main part of the hy- 

 pophysis, the anterior lobe, is a short oval mass lying below the 

 infundibular outgrowth (fig. 48) . As in late embryos, the pars 

 intermedia forms a layer around the infundibular outpouching. 

 The distal portions of the lateral lobes lie against the floor of the 



l 1 igs. 27 to 29 Transverse sections of an alligator embryo. X 40 (R. C. 9, pos- 

 sibly over 30 mm. long). Fine stipple, anterior lobe; coarse stipple, lateral lobes; 

 lined, pars intermedia; black, brain and infundibulum. 



brain and are connected with the proximal parts by means of 

 small stalks which descend caudalward over the top of the an- 

 terior lobe (figs. 30 to 32) . The proximal parts he to either side 

 of the anterior lobe and are continuous ventrally with the caudal 

 part of it (fig. 33). The anterior lobe ends cranially in a blunt 

 apex, separated from the floor of the brain by connective tissue, 

 and caudally often in two blunt points separated by the anas- 

 tomosing branch of the cerebro-carotid arteries (fig. 48). The 

 upper of the caudal points continues caudalward below the pars 



