THE PITUITARY BODY 



Much has been written about the relationship or lack of 

 relationship among the different cells. Most investigators be- 

 lieve that the oxyphils and basophils are morphologically 

 different types of cells. There is much less agreement as to 

 the relationship of the reserve cells to the chromophils. The 

 beliefs of different authors have been illustrated and dis- 

 cussed by Severinghaus (1933). On the basis of studies of the 

 Golgi apparatus in the rat, he concluded that the reserve 

 cells were of two types: one ultimately differentiated into an 

 oxyphil cell, the other into a basophil. The most important 

 of other interpretations as well as references to some of the 

 literature of this field can be found in Severinghaus's paper. 



The pars intermedia. — The greater part of the pars inter- 

 media of mammals lies between the pars glandularis and the 

 pars neuralis. Usually, also, the residual lumen of Rathke's 

 pouch (Kolliker's space), containing a homogeneous eosin- 

 staining material ("colloid"), separates at least part of the 

 pars intermedia from the pars glandularis. In adult human 

 beings the space may be absent. The pars intermedia is 

 readily identified in children. In adults it appears to be a 

 rudimentary structure at most. In other mammals, the pars 

 intermedia usually is a clearly defined structure. Often cords 

 of cells from the pars intermedia invade the adjacent pars 

 neuralis. 



A photomicrograph of the pars intermedia of the monkey 

 is reproduced in Figure 8. 



The cells of the pars intermedia have been studied by 

 many investigators by a variety of cytological techniques.^ 

 Generally they are described as non-granular basophils differ- 

 ing in morphology, however, from the basophils of the pars 

 glandularis. Maurer and Lewis (1922) described two types of 



^ The following are references to some of the recent literature: Dayton, Schonig 

 (1926); Guizzetti, Urasov (1928); Rasmussen (1928-30, 1933); Marburg (1929); 

 AschofF, Pietsch (1930); Maeda (1931); Kraus (1932); Roussy and Mosinger (1934); 

 and Beato (1935). 



[16I 



