MENTAL DIFFERENCE AND DISORDER 215 



causes equally of colic and mania in the horse (Girard and 

 Pierquin). 



The influence of entozoa as a source of cerebral disturb- 

 ance, including insanity, has been pointed out in this 

 country by Cobbold. The possible presence of intestinal 

 parasitic worms, of nematode entozoa, as a cause of conjoint 

 mental and physical disorder, is a subject deserving to be 

 kept constantly in mind by veterinarians ; for there can be 

 no doubt that the effects of their presence are frequently 

 mistaken for rabies or other supposed incurable forms of 

 madness or distemper, and the lives of valuable animals 

 such as the horse, ox, and dog are sacrificed to this pro- 

 fessional error. According to our first, and indeed our only, 

 British authority on the entozoic diseases of man and other 

 animals, worms in the lower animals produce the following 

 group of symptoms : General cerebral disturbance ; appa- 

 rent bewilderment ; uncertainty of movement ; convulsive 

 twitchings ; deafness ; dumbness ; amaurosis ; mental im- 

 becility ; mania ; and paralysis all of which symptoms 

 may be dissipated, the seemingly serious disease cured, by 

 the simple remedy of an aperient. On the other hand, how- 

 ever, worms in the dog may produce no symptoms at all, or 

 symptoms that are as sudden in their incidence as fatal in 

 their issue (Cobbold) . 



Other foreign bodies appear to act simply as mechanical 

 irritants, as in the case of a dog at Macclesfield that 'was 

 driven mad from a pin having pierced, and become fixed in, 

 the stomach ' (Berkeley). 



A thoroughly competent writer (Walsh) describes in-and- 

 in breeding in the dog as resulting, or liable to result, in the 

 offspring, in 



1. General excitability. 



2. Uselessness for work. 



3. Delicacy of physical constitution. 



4. Want of mental capacity, mental imbecility, or 



5. Complete idiocy. 



Gillmore mentions, as the result of breeding from a 

 nephew in a sporting dog, that ' the entire litter were idiots, 

 or at least so deficient in brains, that out of eight which I 



