24 



INHERITANCE. 



Chap. XII. 



C^ 



two sons were microphthalmia on the same side. 62 In all such 

 cases, if truthfully reported, in which the parent has had an 

 organ injured on one side, and more than one child has been 

 born with the same organ affected on the same side, the chances 

 against mere coincidence are enormous. But perhaps the most 

 remarkable and trustworthy fact is that given by Dr. Brown- 

 Sequard, 63 namely, that many young guinea-pigs inherited an 

 epileptic tendency from parents which had been subjected to 

 a particular operation, inducing in the course of a few weeks 

 a convulsive disease like epilepsy : and it should be especially 

 noted that this eminent physiologist bred a large number of 



;'uinea-pigs from animals which had not been operated on, and 





not one of these manifested the epileptic tendency. On the 

 whole, we can hardly avoid admitting, that injuries and muti- 

 lations, especially when followed by disease, or perhaps exclu- 

 sively when thus followed, are occasionally inherited. 



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, 64 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, 

 herited 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 plants, a long catalogue of in- 



Causes of Non-inheritance. 



* 



A large number of cases of non-inheritance are intelligible on 



to 



the principle, that a strong tendency to inheritance does exist, but 



62 



This last case is quoted by Mr. by Mr. Baker in ' The Veterinary/ vol. 



xiii. p. 723. Another curious case is 



British and Foreign 



Sedgwick in 



Medico-Chirurg. Keview/ April, 1S61, given in the ' Annates des Scienc. Nat./ 



p. 484. For Blumenbach, see above- 1st series, torn. xi. p. 324. 



cited paper. See, also, Dr. P. Lucas, 63 'Proc. Eoyal Soc.,' vol. x. p. 



'Traite de THered. Nat./ torn. ii. p. 297. 



492. Also ' Transact. Linn. Soc.,' vol. 



ix. p. 323. Some curious cases are given Journal/ April 18, 1863. 



64 Mr. Sproule, in 'British Medical 







that 



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