40 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 93 



p. 35) says that their implantation is various, ranging from large 

 diffuse to one or even more than one " pedicules ". Korner (1904. 

 p. 106) believed that " the globular growths tended to be located more 

 outwardly than the small buttonlike exostoses, to arise from the pos- 

 tero-superior wall of the canal, to be larger than the other excres- 

 cences — pea to cherry size — and to lead readily to the complete clos- 

 ure of the meatus." Moller-Holst (1932, p. 96) says: "As to the 

 shape, one can distinguish flat, broadly based, semiglobular, globular, 

 and pedunculated exostoses. All the forms connect through inter- 

 mediary grades." 



Nezi' observations. — In our examinations it was found that the 

 ear exostoses show a variety of forms which merge into each other, 

 present no distinct separate classes, and can only be subdivided roughly 

 or arbitrarily. They range on one hand from what can clearly be 

 recognized as an abnormal localized tumefaction or bulge on the pos- 

 terior or anterior tympanic wall to large irregular massy growths with 

 adventitious smaller elevations ; from slight oblong ridges directed 

 along the axis of the canal to redundant more or less conflowing welts ; 

 from a recognizable swelling of the postero-superior or antero- 

 superior terminal part of the tympanic ring or bone, to masses that 

 almost occlude the auditory canal ; and from little pearllike exostoses 

 to more or less buttonlike or pedunculated and irregular tumors, 

 some of which nearly occlude and some even protrude from the 

 meatus. On the other hand, there were observed no slender spines, 

 or sharp osteophytic growths, and ncj forms that could properly be 

 called " cylindrical ". 



SYMMETRY 



There are repeated statements in the literature on ear exostoses that 

 these growths in some cases occur symmetrically in the two ears of the 

 same individual. Thus Dalby (1876) states that "not infrequently 

 both meatus are affected similarly, not only in respect to the presence 

 of these tumors, but also as to their size and number " ; and they may 

 also " increase synchronously " in the two canals. For Delstanche 

 ( 1878, p. 10) " most often, in case the tumors are bilateral, their point 

 of insertion corresponds exactly in the two canals, and they possess 

 also a certain analogy of form and even of size." Ayres (1881) says, 

 " There is seemingly a good deal of uniformity in their development " ; 

 and similarly Kessel (1889, p. 286) states, " as to the bilateral cases, 

 it may be remarked that they occasionally appear in the same form 

 and in the same locations and therefore symmetrically " ; and for 

 Schlomka (1891, p. 16) the bilateral outgrowths "are occasionally 



