a predisposition inherited more frequently from the mother 

 than from the father; moreover, it has frequently been 

 observed that when several families have resided under 

 the same roof, and under similar circumstances, none of 

 the children became rickety except those whose fathers or 

 mothers had suffered from rickets during their childhood. 

 Besides, as a further evidence of an inherited predisposition, 

 numerous cases of fcetal or congenital rickets have been 

 observed under circumstances which negatived the possibility 

 of any syphilitic or placental influence. As shewing 

 metamorphoses in transmission, I may mention the fact that 

 other constitutional diseases in the parents may contribute to 

 the production of rickets in their offspring ; thus Ritter von 

 Rittershain alleges chronic tuberculosis in the father as a 

 predisposing cause of some importance. Among the parents 

 of seventy-six rickety children whose family history he 

 investigated, he found seven tuberculous fathers and four 

 tuberculous mothers. In the same way many facts are 

 forthcoming to support the opinion that constitutional syphilis 

 in the parents also predisposes to rickets in the clildren, 1 

 and thus heredity acts, mysteriously and potently with 

 variability, acts and interacts, preserving and perpetuating 

 the commonhealth of the community, as it preserves and 

 perpetuates the characteristics of the race by varying and 

 differentiating the individual. 



Of the remaining diseases of the locomotive apparatus, I 

 have still to refer to that very rare disease, osteo-malakia or 

 mollities ossium, which has also been termed " rickets of the 

 adult." Alluding to this, Mr. Hutchinson says "Respecting 

 a certain number of the best marked cases, there appears 

 good reason to believe that the disease is really a form of 

 1 Senator. 



