GENETIC TYPE AND THE ENDOCRINES 273 



appears in many different species of animals, including man 

 himself. 



The general appearance and behavior of persons with this 

 bulldog-like depression of the face and consequent protrusion 

 of the lower jaw have led physicians to suspect an associa- 

 tion between these modified features and either a defective 

 or disturbed endocrine system. The bulldog type of face and 

 head, as found in the human race, is usually confined to short, 

 stocky, dwarfed persons with abnormally shortened extremi- 

 ties. The behavior of such persons may be loosely diagnosed 

 as stolid and deliberate, and the more intelligent among them 

 are recognized as strongly determined in their actions. In 

 popular parlance, they arc said to have ''bulldog tenacity." 

 There have been very few reports on either the morphology 

 or physiology of the endocrine glands from such human 

 individuals. A number of years ago Symmers and Wallace 

 ('13) recorded the abnormal condition of the glands and 

 other tissues from an adult achondroplasia dwarf with bull- 

 dog typed face and head. The thyroid in this individual 

 showed well marked modifications. 



The general morphology and the behavior of bulldog typed 

 individuals are so consistently uniform that they deserve 

 serious investigation. This type probably offers the most 

 valuable material available for an analysis of the relation- 

 ships between morphologic form and nervous functions. For 

 such reasons it is important to know whether the bulldog 

 head has a similar origin and whether it develops on a com- 

 mon plan in all the many different animal species in which 

 it is found. 



We may again refer to plate 38 (p. 233), and to plate 50, 

 for clear illustrations of the wide differences between the 

 normal long skull and the modified bulldog typed skull. In 

 plate 50 the skulls of the German shepherd dog and the 

 English bulldog have been photographed from three aspects. 

 In lateral view, the abbreviated face, increased skull height 

 and enormously protruding mandible of the bulldog skull 



