GENETIC TYPE AXD THE EXDOCIUNKS 453 



toxylin and eosin and a modified Mallory stain, the acidophiles 

 and basophiles can be quite definitely differentiated after a 

 certain degree of practice. From experience with well stained 

 specimens, one becomes familiar with the size, shape and 

 general position of the basophiles as contrasted with acido- 

 philes, and is enabled to distinguish them with considerable 

 accuracy even in specimens not clearly stained. The acido- 

 philes, as is well known, stain much more constantly and 

 distinctly than the basophiles. 



The nature of our study up to the present stage, as well 

 as the wide variation in relative proportions of pituitary cell 

 types in many pure breeds, has not warranted a minute 

 cytological examination of the chromophobes in order to esti- 

 mate their tendency towards one or the other chromophilic 

 types, as Severinghaus ('38) has so beautifully demonstrated 

 to be possible on the basis of the form and position of the 

 Golgi apparatus in relation to the cell nucleus. The histo- 

 pathology of these pituitaries seems to present sufficiently 

 important deviations from the normal in such wide variety 

 as to fully tax our present knowledge of endocrinic functions 

 in attempting to unravel the consequences of these conditions. 



The relative proportion of acidophiles to basophiles was 

 eleven to one for the pituitary shown in sagittal section in 

 figure 1, plate 87. The counts were made on three well spaced 

 longitudinal sections. The basophiles are more abundant and 

 exist in higher proportions through the mid-ventral region 

 than elsewhere. The cytoplasm of some of the basophiles 

 contains well stained rods or fibers rather than granules, 

 although the fixation is good and the basophile nuclei are 

 perfectly preserved. 



The finer structure of the pars intermedia in this specimen 

 is irregular, and there are many colloidal follicles of small but 

 various sizes. The pars nervosa is extensive and fibrous in 

 appearance. The entire pituitary may be classed in general 

 as quite normal. 



The three other photomicrographs of dachshund pituitaries 

 given in plate 87 illustrate the morphologic variations which 



