QUESTION OF PHYSICAL DEGENERATION 251 



disease would have passed off without working permanent harm. 

 Those who have come to the conclusion that no acquired 

 characters are transmitted can find unmistakable evidence of this 

 in the fact that so-called acquired deafness tends to be inherited, 

 though to a much less extent than deafness which is not the 

 result of disease. To explain this, we might assume that the 

 diseases which cause deafness find out a congenital weakness in 

 the ear or the connected air-passages, and so destroy the sense, 

 whereas they would have left a perfectly healthy organ unim- 

 paired. Competent judges, however, hold that this view is in 

 most cases incorrect ; that measles or scarlet fever may ruin the 

 most perfect of ears, though bad consequences are rendered far 

 more probable by a general weakness of constitution. Never- 

 theless there may be almost undoubtedly is local weakness in 

 some of the cases, in which inflammation destroys the sense of 

 hearing : the upper air-passages may be much subject to catarrh, 

 thus giving disease a better grip. This local weakness may be 

 inherited, and may lead to deafness in successive generations. 

 Again, hearing, already defective at birth, may be further 

 reduced by inflammation due to fever, so that, at last, little of 

 the sense may remain. Such a case would probably be put 

 down as one of adventitious deafness. Whereas if the organs 

 had been originally perfect, the reduction would have left a 

 moderate power of hearing, and the person in question would 

 not have been counted among the deaf. Moreover, a tendency 

 to develop adenoid bodies undoubtedly runs in families, and these 

 not unfrequently lead to loss of hearing. Deafness due to this 

 cause, since not present in infancy, might easily be put down as 

 adventitious, even if the adenoids were undetected. In this 

 case, then, a congenital defect is transmitted, and the "adventi- 

 tious " deafness is only a symptom of the defect. In fact, whether 

 the evil is traceable to fever or to adenoid growths, we are able 

 to account for the reappearance in the same family of a character- 

 istic that is described in the returns as acquired. 



We can now go on to consider deaf-dumbness in its relation to 

 the question of physical degeneracy in civilised peoples. The 

 first important point to notice is that the loss of hearing is in 



