All Analysis of the Juxta-Neural Epithelial Portion etc. 271 



rule and presents two general divisions, one tliat is vertical [9a\ and 

 the other oblique [91)]. 



The caudal surface is relatively deep and merges with a long 

 pre-mamillary area [6]. The infundibulum [10] is continued caudad 

 by a stem of considerable length at the extremity of which is the 

 solid, expanded processus infundibuli [11\. The recessus tuberis [1?"\ 

 and the recessus infundibuli [<9] are both present but there is no 

 cavity in the infundibular process. 



The three epithelial constituents of the gland occupy their typical 

 positions. The pars tuberalis [12] surrounds the eminentia saccularis 

 [P] and the infundibulum [10] with the exception of the stem of the 

 latter. The pars infundibularis [13] invests the stem of the infun- 

 dibulum and the processus infundibuli [11\. The dorsal surface of 

 the infundibular process is covered by a much attenuated layer of 

 epithelium while its ventral covering is thick and dense. A well 

 marked residual lumen [15] separates the pars distalis [li\ from the 

 pars infundibularis [13]. 



1. Histological characters of the pars tuberalis (plate XVII, flg. 35). 



a) Cellular arrangement. The cellular arrangement is that of 

 cell masses with occasional small, thick- walled acini. 



b) Cells. The cells are all basophilic, the cytoplasm very scanty 

 and granular, the nuclei picnotic and centric. 



c) Vascularity. The vascularity is not marked. 



2. Histological characters of the pars infundibularis (plate XVII, 

 fig. 37). 



a) Cellular arrangement. The cellular arrangement is that of 

 dense cell masses. 



b) Cells. The cells are of faintly basophilic type with a rela- 

 tively large amount of homogeneous cytoplasm and large vesicular nuclei. 



c) Vascularity. Scarcely any vascular elements are present. 



3. Histological characters of the pars distalis (plate XVII, fig. 36). 

 a) Cellular arrangement. The cellular arrangement is that of 



convoluted cell cords. 



bj Cells. The cells are acidophilic with ample cytoplasm, and 

 large vesicular nuclei. 



