466 



INHERITANCE. 



Chap. XII. 



two deaf and dumb children were produced. Mr. Sedgwick, 53 

 in commenting on this remarkable and fortunate failu;e in 

 the power of transmission in the direct line, remarks that it 

 may possibly be owing to " excess having reversed the action 

 of home natural law in development." But it is safer in the 

 present state of our knowledge to look at the whole case as 

 simply unintelligible. 



Although many congenital monstrosities are inherited, of 

 which examples have already been given, and to which may 

 be added the lately recorded case of the transmission during 

 a century of hare-lip with a cleft-palate in the writer's own 

 family, 54 yet other malformations are rarely or never inherited. 

 Of these latter cases, many are probably due to injuries in 

 the womb or egg, and would come under the head of non- 

 inherited injuries or mutilations. With plants, a long cata- 

 logue of inherited monstrosities of the most serious and 

 diversified nature could easily be given ; and with plants, 

 there is no reason to suppose that monstrosities are caused 

 by direct injuries to the seed or embryo. 



With respect to the inheritance of structures mutilated by 

 injuries or altered by disease, it was until lately difficult to 

 come to any definite conclusion. Some mutilations have been 

 practised for a vast number of generations without any in- 

 herited result. Godron remarks 55 that different races of man 

 have from time immemorial knocked out their upper incisors, 

 cut off joints of their fingers, made holes of immense size 

 through the lobes of their ears or through their nostrils, 

 tatooed themselves, made deep gashes in various parts of their 

 bodies, and there is no reason to suppose that these mutila- 

 tions have ever been inherited. 56 Adhesions due to in- 



53 ' British and Foreign Med.- 

 Chirurg. Review,' July, 1831, pp. 

 200-204-. Mr. Sedgwick has given 

 fcuch full details on this subject, with 

 ample references, that I need refer 

 to no othei authorities. 



54 Mr. Sproule, in ' British Medical 

 Journal,' April 18, 1863. 



55 'De l'Espece,' torn, ii., 1859, p. 

 299. 



5G Nevertheless Mr.Wetherell states, 

 'Nature,' Dec. 1870, p. 168, that 

 when he visited fifteen years ago the 

 Sioux Indians, he was informed " by 

 a physician, who has passed much of 

 his time with these tribes, that some- 

 times a child was born with these 

 marks. This was confirmed by the 

 L T . S. Government Indian .Agent." 



