94 DIRECT INJURIES CAUSED BY INSECTS. 



Acarus Scahiei ; an opinion which he repeats in his late 

 work on Cutaneous Diseases ; and which, according to 

 Hermann'', has been also rendered unquestionable by 

 Wichmann in his Etiologie de la Gale (Hanovre 1786), 

 a work I have not had an opportunity of consulting. 

 From all this we may regard the point as so far settled, 

 that such an animal exists at least as an occasional con- 

 comitant of scabies. 



This fact being ascertained, a more complex inquiry 

 remains, which branches out into two distinct ques- 

 tions. Is scabies always produced by these insects ? 

 Or, if this be not the case, Is the animate scabies a 

 distinct disease from the inanimate ? 



It is very remarkable that Linne, a physician as well 

 as a naturalist ; and De Geer, one of the most accurate 

 observers that ever existed ; should both assign the in- 

 sect in question as the undoubted cause of the common 

 sca])ies of their country : the one applying to the dis- 

 ease he was speaking of the epithet of communissima^ 

 and observing the fact to be notorious, (cuique liquet,) 

 and the other designating it by its Avell known French 

 name " La Gale^.''^ And is it not equally remarkable 

 that such men as John Hunter, Dr. Heberden, Dr. 

 Bateman, Dr. Adams, and Mr. Baker should never, 

 in this country, have been able to meet with it? Did 

 it indeed exist in our common scabies, it seems impos- 

 sible that it could have escaped the observation of the 

 two last of these gentlemen; Dr. Adams being so well 



* Mem. Apterolagique, 79. 



''I am infi)rmf"d bv mv learned friend Alexander MacLeay, Ksq. Se- 

 cretary to the Linnean Society, that, in the north of Scotlaud, the insect 

 of the itch is well known, and easily discovered and extracted. 



