244 MIXED CAUSES OF 



stitutional tendency or proclivity to mental derangement; 

 morbid mental peculiarities of all kinds themselves, vices of 

 temper, unnatural fears, a disposition to panic or panpliobia, 

 unaccountable dislikes, the mental consequences of ill-usage 

 or hard work, and all manner of evil habits, are transmitted 

 from parent to offspring. Thus we read of the hereditary 

 transmission of the nervous temperament in the bitch (Walsh); 

 of aversions or antipathies in the cat and dog ; of various 

 forms of vice in the horse, cow, bull, heifer ; of strong im- 

 pulse with feeble will; and of other indications of faulty 

 mental organisation. As in man, mental unsoundness is to 

 be regarded as the most certain of all the hereditary neuroses. 

 Accidents of birth or ancestry, especially what is called high 

 blood or breeding in such animals as race-horses or sport- 

 ing dogs, in whom there is an accumulation in successive 

 generations of the conditions summed up in the comprehen- 

 sive term 'nervousness,' are, as in man, among the most 

 fertile of the remote or predisposing causes of mental dis- 

 order. Among hereditary forms of mental defect or disorder, 

 idiocy has to be included (McBride), and it is one of the 

 forms that result too frequently, in an animal's ancestry, from 

 man's ill-usage. 



It would appear, then, that the study of an animal's 

 antecedents, of its family history, of the mental condition of 

 an ancestry is quite as necessary or desirable as in man in 

 determining, or endeavouring to determine, the etiology of 

 insanity, or the power for good or evil of ancestral influences. 

 For a bias is given to the whole organisation, including the 

 nervous and mental, by heredity. 



Veterinarians speak of irritable, surly, and vicious tem- 

 peraments or dispositions as specially conducive to the 

 development of insanity in the lower animals (Fleming) ; 

 while, as in man, we meet with the melancholic, phlegmatic, 

 nervous, and sanguine temperaments, with all their combi- 

 nations and modifications. 



All forms of artificial, and especially of luxurious, life, 

 by reason of the unnatural, unhealthy habits involved, are 

 seriously damaging to mental soundness. Hence we find all 

 forms of mental excitement and depression, all infirmities of 



