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Epilepsy. The hereditariness of a predisposition to this 

 affection is beyond all doubt, as is acknowledged by every 

 authority who has written upon it. The predisposition itself 

 may be transmitted directly from parent to child, or it may 

 remain latent in a generation or two, and appear in the 

 grandchild or great-grandchild \ moreover, it may be trace- 

 able only in the collateral branches of the ancestry, as in 

 hereditary maladies. Predisposition may also be connected 

 with congenital formation, as is often evidenced in cases of 

 chronic hydrocephalus, also in those in which there is a 

 misshapen or unsymmetrical form of the head. Amongst 

 other predisposing causes may be mentioned the scrofulous 

 diathesis and idiosyncrasy ; also the epochs of childhood 

 and puberty, at which periods the nervous and muscular 

 systems attain their maximum of sensibility and irritability, 

 and the physical susceptibility is greatest. With regard to 

 the influence of the scrofulous diathesis, Dr. Cheyne holds 

 that epilepsy is as certain a manifestation of the strumous 

 disposition as tubercular consumption, or psoas abscess ; but 

 it may be observed that the strumous diathesis, and a parti- 

 cular conformation of the head, are both very likely to 

 descend from parents to their children. 1 In those cases of 

 epilepsy which are hereditary, the affection is usually 

 developed at an earlier age. In the great majority of cases 

 epilepsy is developed between ten and twenty years of age, 

 and especially at or about the period of puberty. According 

 to Echeverria, the occurrence of the symptoms of hereditary 

 epilepsy is before puberty ; according to Reynolds, not later 

 than the twentieth year. It may, therefore, be assumed that 

 an individual with an hereditary predisposition, remaining 

 healthy up to the twentieth year, will also escape epilepsy 



i Watson. 



