GENETIC TYPE AND THE ENDOCRINES 511 



its deep depression at the nasion and extremely undershot 

 jaw, illustrated in plate 57 (fig. 10). As previously pointed 

 out, the acromegalic-like overgrowth of the skin was the most 

 remarkable feature presented by this dog. The most excessive 

 skin area was about the head and anterior regions of the 

 body, and this was sufficient to cover an animal of twice this 

 dog's size. Is the extreme acidophilic nature of the pars 

 distalis related to the disharmonious growth distortion! 



A longitudinal section of the pituitary from a third F 2 

 hybrid brother is shown in figure 4 (pi. 96). This gland is 

 from 1147 S , an eccentric type among the F2 bassethound- 

 bulldog hybrids in that it resembled more nearly the acro- 

 megalic giant St. Bernard form than either parental stock. 

 The skull of this dog is shown in plate 57 (fig. 19) and was 

 closely similar in its indices to the skull of 9915 (fig. 14). 

 No. 991 $ is of a more pronounced St. Bernard type, as 

 shown by photograph from life in plate 58 (fig. 1) (p. 323). 

 The close similarity of the skulls from these two St. Bernard 

 typed bassethound-bulldog hybrids to that of the pure St. 

 Bernard acromegalic skull is clearly shown in plate 57. 



The pituitary gland of the St. Bernard-like animal, 1147 $ , 

 differs in several respects from the gland of the bulldog-like 

 1145 $ , and also from that of 1146 $ with its mastiff typed 

 head. The pars nervosa is not of bulldog type and the pars 

 intermedia differs from the other two specimens by showing 

 many small follicles filled with colloid-like pink staining ma- 

 terial, a character more common among the larger breeds 

 than the smaller. The pars tuberalis is extensively invaded 

 by diverticula from the residual lumen, which is a frequent 

 characteristic of the St. Bernard hybrids, as we shall see 

 beyond. A large branching cyst is present in the pars distalis 

 and the cellular arrangements and proportions of this part 

 exhibit most striking characteristics. The epithelial cells are 

 in many regions more compact than in the glands of the 

 bulldog and mastiff typed animals. At first glance, every 

 epithelial cell seems to be an acidophile, there being very few 



