92 DIRECT INJURIES CAUSED BY INSECTS. 



In the instance here recorded, the dysentery, or diar- 

 rhoea, was evidently produced by these Acari; but it 

 would be going too far, I apprehend, to assert that 

 they are invariably the cause of that disease. 



That Scabies, or the itch, is occasioned by an Acarus 

 is not a doctrine peculiar to the moderns. INIoufFet 

 mentions Abinzoar, called also Avenzoar, a celebrated 

 Hispano-Arabian physician of Seville, who flourished 

 in the twelfth century, as the most ancient author that 

 notices it. He calls these Acari little lice that creep 

 tinder the skin of the hands, legs, and feet, exciting- 

 pustules full of fluid ^. Joubert, quoted by the same 

 author, describes them under the name of Siro7ics or 

 mites, as always being concealed beneath the epidermis, 

 under which they creep like moles, gnawing it, and 

 causing a most troublesome itching. It appears that 

 Mouffet, or whoever was the author of that part of the 

 Theatrinn Insectorum, was himself also well acquainted 

 with these animals, since he remarks that their habita- 

 tion is not in the pustule but near it : a remark after- 

 wards confirmed by Linnc'', and more recently by 

 Dr. Adams'". In common with the former of these au- 

 thors, Moufffet further notices the effect of warmth upon 

 them in exciting motion '^ Our intelligent countryman 

 also observes that they cannot be Pediculi, since they 

 live under tlie cuticle, which lice never do"". In the 



" Mouffft, 266. 



'' Acarus sul) ipsa pustula minime qiucrendus est, sed longius rccessit, 

 sequendo nigam cuticula! observatiir. ylmoon. Ac. v. 95. not.**. 



* Observaliom, &c. 296. 



° Extractus acu et s.upor iinguc positus, movet se si solis ctiam calore 

 adjuvetur. ubi supr. Ungui impositus vix movetiir: si vero oris calido ha- 

 litn affletnr, agilis in ungue cursitat. Fn. Suec. 1975. 



* Neque Syrones isti iunt de pediculoriun gencre, ut Joannes Langius 



