THE PARS BUCCAL1S OP THE HYPOPHYSIS 71 



ependyma with an ectally placed prominent stratum of neuro- 

 pilem (fig. 28). In the albino the saccular wall and lateral 

 processes and pituitary wall all exhibit the membranous type 

 of structure (fig. 29). The pituitary floor, which is normally 

 in contact with the epithelial hypophysis and which has been 

 deprived of such contact by the epithelial hypophysectomy, 

 thus exhibits the same type of structure as those portions not 

 normally in contact with this epithelial component of the hy- 

 pophysis. Directly attributable to the membranous character 

 of this pituitary floor are invariably seen certain pronounced but 

 irregular folds which appear in this structure in the albino (fig. 

 26), but not in the normal animal (fig. 25). Although such 

 foldings are undoubtedly due to the technical procedure incident 

 to the preparation of this material, yet the membranous nature 

 of the infundibular floor of the albino is directly conducive to 

 them, while the firmer structure of the normal infundibulum 

 prevents them. 



The abnormality in the infundibular process in the albino 

 is not limited to the pituitary floor, for it is very evident that 

 the neural lobe in the albino as compared to the normal animal 

 of corresponding dimensions (table 6) is also diminished in size, 

 a diminution which varies from 40 per cent to 80 per cent and 

 which transcends very distinctly the considerable variability 

 which this lobe exhibits in both types of specimens. 37 Asso- 

 ciated with this diminution in size is a profound alteration in 

 the shape and position of this lobe. Instead of the symmetrical, 

 transversely placed, dumb-bell-shaped lobe of the normal (fig. 

 25), this dwarfed lobe is oval, asymmetrical in shape and posi- 

 tion, and has no great transverse extent (fig. 20). Normally 

 attached somewhat dorsally to the apex of the iniandibular 

 process and thus abutting and being attached to its dorsal sur- 

 face, in the albino it is constantly found grasping the apex of 

 this process and extends invariably slightly onto the pituitary 



37 It does not appear from figures 28 and 29 that the neural lobe of the albino is 

 smaller than in the normal. It must be kept in mind, however, that due to the 

 difference in the shape of this lobe in the two types that a median sagittal section 

 passes through its smallest dimension in the normal animal, and through its max- 

 imum sagittal diameter in the albino (figs. 25, 26). 



