Studies on the EIndocrine (Jlands 331 



contains vacuoles of various size. The}' have larj^e nuclei (O/x to lO/x), 

 honio<;eneously but faintly stained by lueuiatoxylin and coloured faintly 

 blue bv Mallorv. These cells are for the most i)art much largrer than the 

 ordinary oxyphil cells, but are probably formed from tlu-m. The}' are 

 scattered about, l)ut art" especially numerous in the middle of the pars 

 antericn-. (Jrdinary oxyphil cells are present in large number. Their 

 cytoplasm is stained red both b}' eosin and by Mallorv. Their nuclei are 

 coloured distinctly by luvmatoxylin. Some are .stained ^-eliow by IMallor}'. 

 Basiphil cells are also present in considerable number. Their cytoplasm 

 is more open than that of the oxyphil cells. It is stained faintly by iu^jma- 



^ 



I . ' . ./^iW *^>^ 



P 







♦ • i^A 



6 



i 



r./, 



V ^4 ... • T-i ^rr.^^ v--^^ 



Fig. 10. — Section of pars anterior of pituitary body of male rat fed with addition to its 

 ordinary food of O'l grni. of potassium iodide per diem during five day.i. Micro- 

 photograj)h ; magnified 500 diameters. Hsmatoxylin-eosin preparation. 



This preparation shows a large proportion of chromaphobe cells containing large 

 nuclei with coarse chromatin granules. 



toxylin and by Mallor}' (blue). The pars intermedia shows a certain 

 number of vesicles containing hyaline substance. There are, however, no 

 distinctive changes in it nor in the pars nervosa. 



Effects of administering the Iodides of Sodium 

 and Potassium in Rat. 



Marked changes occur in the pars anterior after administration of sodium 

 iodide or potassium iodide (fig. 10). Under a low power the pars anterior 

 is congested ; the glandular substance has a compact appearance. There is 

 a striking increase in the number of chromaphobe cells, with a similar 

 reduction in the chromaphils (both oxyphils and basiphils). The cell- 



