502 CHARLES R. STOCKARD AND E. M. VICARI 



extensive thin roof in order to obliterate the exaggerated 

 hypophyseal lumen. The small size of the future pars distalis 

 area is only long enough to surround the ventrolateral part 

 of the disproportionately large pars nervosa ; its dorsal region 

 is entirely free. The photomicrograph in plate 95 serves to 

 illustrate these peculiarities. 



In the human, the infundibular portion and the pars inter- 

 media of the pituitary have been found to be larger in the 

 male than in the female and, as pointed out by Rasmussen 

 ('38), this relation probably holds for other mammals as 

 well. At the same time, the pituitary as a whole is larger in 

 women than it is in men, a condition due entirely to the larger 

 pars distalis of the female gland. On the basis of such find- 

 ing's, the pituitary gland of the bulldog with its small pars 

 distalis and disproportionately large pars intermedia and pars 

 nervosa may be classed as strongly of the male type. It will 

 be shown in later discussions on behavior that the female 

 bulldog produces only small litters of puppies and displays 

 definitely defective maternal instincts. This may be due in 

 part to the masculine proportions of the pituitary gland. 

 Yet there is also frequent histopathology in the tuberalis 

 and distalis of the bulldog gland, as well as low basophile 

 counts, and these conditions could account for such dis- 

 turbances. 



Figure 2 (pi. 95) illustrates an almost sagittal section of 

 the pituitary from a bulldog of 2| years, 1083 9 . The animal 

 was a prize typed bulldog in spite of the fact that the localized 

 achondroplasic condition in the basicranium had become some- 

 what generalized to involve the cervical vertebrae, causing 

 ankylosis and a slight bend in the neck of the animal. 



The pars nervosa of this pituitary is solid and almost 

 spherical in shape. The third ventricle extends through the 

 infundibular stalk only, and not into the nervosa, as is the 

 case in some breeds. The distalis, as well as the intermedia, 

 is intimately fused with the posterior pole of the nervosa, 

 and cells from these portions invade the nervosa. Arrested 



