574 



THE DUCTLESS GLANDS ENDOCRIN GLANDS 



Tilney (Internationale Monatschrift f. Anat. u. Phys., Bd. 30, 1911), 

 including careful reconstructions of a number of mammalian hypophyses, 

 shows that this description is incomplete. The form, extent, relation 

 and genetic significance of the pars intermedia had apparently hitherto 

 not been fully appreciated, though Herring (1908) had already called 

 attention to the fact that it comprised two histologically different areas. 

 Tilney divides the hypophysis into: (I) pars neuralis (pars nervosa) ; 



13 15 



FIG. 492. SAGITTAL VIEW OF A WAX RECONSTRUCTION OF THE HYPOPHYSIS CERE- 

 BRI OF THE ADULT CAT. 



1, third ventricle; 9a and 6, eminentia saccularis; 6, area premammillaris; 5, cor- 

 pora mammillaria; 12, pars tuberalis; 8, recessus infundibuli; 10, infundibulum ; 13, 

 pars infundibularis; 16, recessus process! infundibuli; 11, processus infundibuli; 

 15, lumen residuale; 14, pars distalis; 17. recessus tuberis; 3, optic chiasm. (Tilney, 

 Internat. Monatschr., Bd. 30, 1913.) 



and (II) pars buccalis. The pars neuralis consists of three distinct 

 elements: (a) the eminentia saccularis of the tuber cinereum; (b) the 

 infundibulum; and (c) the infundibular process. The pars buccalis 

 consists of two elements: (a) the pars juxta-neuralis in close relation 

 with and investing the neural portion; and (b) the pars distalis. A 

 cleft, the residual lumen, remnant of the original cavity in the buccal 

 diverticulum, appears between the two. Further analysis of the juxta- 

 neural portion of the gland reveals two histologically different parts: 

 (1) the pars infundibularis completely investing the infundibulum 



