OUR FACE FROM FISH TO MAN 



abnormal human types and of Stockard on the 

 paralleHsm between abnormal human and animal 

 types are all leading to a new understanding of 

 the causes of racial and individual types of faces. 

 The bulldog and a certain type of human dwarf 

 with a broad face and retrousse nose equally owe 

 their peculiar features to a derangement of the 

 normal functioning of the hypophysis, one of the 

 growth-regulating glands. This condition is called 

 achondroplasia and is largely hereditary. In both 

 the bulldog and the achondroplastic dwarf the 

 base of the skull ceases to grow and becomes ossi- 

 fied at an early stage. The rest of the growing 

 head, being confined at the base, grows out at the 

 side and the head thus becomes short in proportion 

 to its width, or brachy cephalic. Similarly the 

 median cartilaginous septum of the nose is not 

 pushed forward by the base of the skull, the bridge 

 of the nose therefore fails to rise up and the nose 

 remains flat or actually sunken, giving a marked 

 depression below the forehead. The maxilla, or 

 upper jaw bone, like the base of the skull, fails to 

 grow forward and this causes the lower jaw to 

 protrude beyond the upper, giving a characteristic 



"undershot jaw." 



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