8 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 93 



The largest series of American crania examined for tympanic ex- 

 ostoses before the present work is that of Russell (1900). It com- 

 prised in all the skulls of 1,369 American aborigines/ which gave 

 the following proportions of exostoses : 



Ear Exostoses in American Aborigines 



Total no. of subjects, 1,369; total no. of skulls with ear exostoses, 104; 

 percent, y.6. 



Russell's comments on the abnormalities are as follows : 



There is a tendency in all races toward the formation of bony tumours or 

 exostoses in the external auditory meatus. The tendency is increased in de- 

 formed crania, though it is now believed that such exostoses are not a necessary 

 accompaniment of deformation ; in support of this it will be noted that the small 

 series of crania from New Mexico with pronounced occipital deformation exhibit 



not a single case of tympanic exostosis The exostoses varied in size from 



minute nodules to large tumorous growths and, in several instances, resulted in 

 complete occlusion of the external auditory meatus. 



Ranke (1900) found, among 21 skulls from Ancon, 3 (14 percent) 

 with ear exostoses. He regarded these as examples of an " endemic 

 disease common to the burial grounds of Ancon as well as those of old 

 Peru in general." * 



Moore ( 1900) reports that ear exostoses are " common in Hawaii ", 

 but gives no data or observations ; and Meyer and Jablonowski ( 1901, 

 p. 75) mention such growths in 2 among 24 crania from Easter Island. 



Le Double and Lebourg (1903) report 9 cases of these growths in 

 46 skulls of American Indians (19.6 percent). Their causation is 

 uncertain : they are evidently neither congenital " as was supposed by 

 Velpeau ", nor of pathological origin. 



In 1904 Korner states that he found ear exostoses at Rostock in 16 

 cases among 2,162 patients with ear troubles, or 0.74 percent ; along the 



'' The printed table contains errors which have here been corrected. The 

 material examined includes that reported on by Blake. 



Eine ftir das Totenfeld von Ancon, wie fiir alle altperuanischen Leichen- 

 statten endemische Erkrankungsform." 



