54 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 93 



or exostoses in the external auditory meatus." A noteworthy state- 

 ment on the subject is that of Gray ( 1910) : 



The other general aspect of the problem is that the majority of individuals 

 never do suffer from exostoses, no matter how badly or from whatever cause 

 their general health become affected, or whether they suffer from some local 

 disease of the ear, such as suppuration, middle ear catarrh, etc., or not. Now 

 it appears to the writer that, viewed from this point of view, the logical con- 

 clusion to be drawn is that the cause of exostoses, that is the condition without 

 which the disease cannot occur, is to be found in the organ of hearing itself, 

 and, further, that this condition exists in the organ of hearing of certain indi- 

 viduals, and in these individuals only. From this point of view, which I believe 

 to be the correct one, exostosis is idiopathic. That is to say, the disease occurs 

 in people who have an inborn tendency to it, and that this is the only constant 

 factor in the etiology. No doubt disturbances, either locally in the ears or 

 constitutionally in the bodies of these individuals, may precipitate the onset of 

 the disease, but no particular one of these disturbances need be present and in 

 many cases they may all be absent. The single constant factor is the innate 

 tendency to the disease and the fact that hereditary influences are evident in 

 many cases is strongly in support of this view. 



Burton (1927) supports Gray's (and others') view of the presence 

 of an " innate tendency " toward these developments, and would call 

 this " atavism ", though evidently with a different shade of meaning 

 from that ordinarily applied to this term. For Moller-Holst (1932, 

 p. 102) a causative connection of atavism is wholly unfounded. 



A few authors approach the conception of a " racial influence ". 

 Thus Darnach (q. by Alexander, 1930) regards the inclination of 

 the American Indian to ear exostoses as a racial peculiarity (char- 

 acter), something like that of the African Negro toward keloid forma- 

 tions. Moller-Holst (1932) is skeptical and would at most admit a 

 " race-peculiarity " (Rasseneigenthiimlichkeit). 



Remarks. — The above and some additional statements of this nature 

 range from hesitating suggestions to firm convictions. They show 

 that the more obvious agencies of the disorder did not fully satisfy 

 these observers. They felt more or less vaguely, or have become defi- 

 nitely convinced, that some innate predisposition, individual or racial, 

 lay in the background of the etiology of the growths under considera- 

 tion. But not one of them has attempted to pin down and critically 

 analyze the hazy factor. 



HEREDITY 



The subjects of " congenitality ", " predisposition ", and " inborn 

 tendency ", considered above, lead inevitably to that of heredity of 

 ear exostoses, and here otology furnishes a line of definite valuable 

 observations. 



