DIRECT INJURIES CAUSED BY INSECTS. 95 



qualified to detect it from his observations in Madeira, 

 and Mr. Baker from Iiis expertness in microscopical 

 researches. Dr. Bateman, in the letter above quoted, 

 says, '•' I liave hunted it with a good magnifier, in 

 many cases of itch, both in and near the pustules, and 

 in tile red streaks or furrovts, but ahvays without suc- 

 cess." In his work on Cutaneous Diseases he tells us, 

 however, that he has seen it, in one instance, when it 

 had been taken from the diseased surface by another 

 practitioner. And though Dr. V/illan in his book 

 speaks of the Acarus astlie concomitant of this disease, 

 yet his learned friend just mentioned observes, that he 

 admitted that tlie insect was not to be found in ordi- 

 nary cases, and indeed never seemed to have made up 

 his mind upon the subject. Wlien I was at Norwich 

 in ISl^, Dr. Reeve very kindly accompanied me to the 

 House of Industry there, to examine a patient whose 

 body M'as very full of the pustules of this disorder ; but 

 though we used a good magnifier, we could discover 

 nothing like an insect. I must observe, however, that 

 our examination was made in December, in severe 

 weather, when the cold might, perhaps, render the ani- 

 mal torpid, and less easy to be discovered. 



From the above facts it seems fair to infer tliat this 

 animal is not invariably the cause of scabies, but that 

 there are cases with which it has no connexion. Now, 

 from this inference, would not another also follow, that 

 the disease produced by the insect is specifically distinct 

 from that in which it cannot be found ? Sauvages and 

 Dr. Adams are both of this opinion*, the former assign - 



* This opinion Dr. Bateman thinks probablj' the true one, Cutan. Dis, 

 19T. 



