452 WILLIAM H. F. ADDISON 



hypophysis, as they are in the corresponding positions in the 

 normal. Thus normal acidophiles of this age measured ll.l/i x 

 9.3 m "with nuclei 6.4^x5.3//, while the experimented acidophiles 

 measured 10.7 n x 8.2 ^ with nuclei 5.6 m x 4.9 ix. There also seems 

 to be a decrease in the staining of the acidophiles, and as they 

 tend to become compressed between the enlarging basophiles, 

 they now play a less conspicuous part in the lining of the blood 

 channels. It should also be mentioned, however, that some- 

 times in the experimented hypophysis is seen an acidophile 

 quite as large as in the normal hypophysis, and that in such a 

 case, it is usually situated on a blood vessel. 



Cell-divisions were found in some sections of both normal 

 and experimented hypophyses of this age. 



Three months after castration {135 days old) 



At three months after castration, large basophiles with vacuoles 

 are seen everywhere throughout the sections. One may ob- 

 serve cells showing intermediate stages in the growth of these 

 large vacuolated cells. 1) Some cells contain one or more small 

 vacuoles, their cytoplasm is coarsely granular, and the nucleus 

 is of spherical shape. 2) As the colloid-like material increases, 

 the nucleus becomes more eccentric and the main part of the 

 cell is made up of the colloid-containing vacuole. 3) Finally, 

 the cells become ring-shaped in section, the cytoplasm forming 

 the periphery of the cell, and containing at some point a more or 

 less flattened nucleus. In these cases nearly the entire cell is 

 constituted of the colloid-like material. Although the baso- 

 philes possessing vacuoles are more numerous than before, they 

 are still outnumbered by the non-vacuolated basophiles. As in 

 the preceding age, just described, many of the non-vacuolated 

 basophiles are little or no larger than normal basophiles of the 

 control hypophyses. These are probably elements which have 

 differentiated more recently than the large vacuolated cells. 



The acidophiles are less conspicuous than in the normal, and 

 this is due partly to their slightly diminished average size and 

 partly to the less intense staining of the acidophilic granules. 



