214 PHYSICAL CAUSES OF 



pelas, of psoriasis, or other skin eruptions, or of other 

 inflammations ; by insect bites, and as a sequel to castration 

 (Pierquin) . 



In short, all bodily disease or disorder, acute or chronic, 

 general or special, produces in other animals as in man 

 aberration of feeling, which may or may not pass into, or 

 amount to, insanity (Maudsley). 



Among familiar examples of animal poisons that produce 

 mental, along with physical, irritation may be specially 

 mentioned insect bites or stings. Horses are ' maddened ' by 

 mosquitos (Brown). The reindeer is also described as ' almost 

 beside itself .... its face and head streaming with blood,' 

 from mosquito bites in the Kanin Peninsula of the Samoyede 

 country (Eae). The effect of the tsetse fly in maddening 

 wild and domestic animals in Central Africa has been gra- 

 phically detailed by Livingstone. Cattle exhibit terror even 

 at the distant sound of this dreaded pest (Figuier). In 

 Abyssinia, according to Prince, the sound of the 6 zimb ' 

 produces similar consternation, the animals refusing food, 

 betaking themselves to wild flight, and death frequently 

 ensuing from fatigue, fright, or hunger, separately or com- 

 bined. 



In our own country, according to Kirby and Spence, 

 Pierquin and other writers, the gad, bot, and breeze-flies 

 beget in the ox, horse, and sheep respectively agitation, 

 anxiety, or distress, excitement, restlessness, alarm, eccen- 

 tric motions or various freaks of conduct, the animals af- 

 fected becoming dangerous from their unmanageability. The 

 mere act of oviposition sometimes induces, besides physical 

 irritation, a frenzy or temporary madness, an ephemeral 

 mania. In the horse the nose-fly produces impatience, 

 restlessness, and torment conditions favourable to accidents 

 to man; while the forest- fly sometimes renders it frantic 

 (White). 



Irritation in distant organs, by producing sympathetic 

 cerebral irritation, is a common cause of mental disturbance. 

 One of the most familiar forms of this so-called eccentric 

 irritation is the presence of worms of various kinds in the 

 intestines. Thus cestridoe and filarics in the stomach are 



