GENETIC TYPE AND THE ENDOCRINES. 13 



as well as a disproportionately heavy lower jaw and over- 

 large hands and feet. Such characteristics constitute well 

 recognized symptoms of the distortion known as acromegaly. 

 Pierre Marie (1889) first recognized that acromegaly in 

 human beings is closely correlated with abnormality and 

 degeneration of the pituitary gland. It is now generally 

 thought to result directly from pituitary disease. Several 

 breeds of dogs constantly exhibit acromegalic patterns, and 

 are bred true for this peculiarity. Both the giant St. Bernard 

 breed and the bloodhound show most exaggerated acromegalic 

 characteristics, having heavy overgrowth of bone and skin 

 along with the functional deficiencies. The large Newfound- 

 land dog is acromegalic to a lesser degree. The members of 

 these acromegalic breeds frequently show considerable modi- 

 fication in the histology of their pituitary glands and dis- 

 tortions of their reproductive processes — characteristics which 

 will be fully considered in following chapters. 



In human beings of ordinary size, acromegalic tendencies 

 with overgrowths are clearly shown at times as an accompani- 

 ment of age degeneration in the pituitary. Occasionally simi- 

 lar conditions appeal- in the normal sized young person, taking 

 the form of unusually large and chubby hands and feet and 

 thickened and furrowed facial features. Among dogs, the 

 bloodhound, although only slightly if at all larger than the 

 wild ancestral types, has developed a most exaggerated acro- 

 megaly of the skin, accompanied by heavy bones and large 

 feet. The skin overgrowth is often more pronounced in the 

 bloodhound than in the acromegalic giant St. Bernard dog. 

 These dogs present many of the physiological symptoms which 

 characterize the human acromegalic, and their voice, postures 

 and behavior are similar to those of their human prototype 

 to an almost uncanny degree. 



Among both dogs and men, dwarf and midget individuals 

 are even more common than giants. These small persons are 

 known to occur in all human races and are to be seen as the 

 commonest freaks of the circus and stage. Dwarf and diminu- 

 tive persons, like the giants, are of two general types. The 



