DIRECT INJURIES CAUSED BY INSECTS. 73 



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 insect in question 

 as the undoubted cause of the common scabies of their 

 country ; the one applying to the disease he was speaking of 

 the epithet of communissima, and observing the fact to be 

 notorious (cuique liquet), and the other designating it by its 

 well 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 impossible that it could 

 have escaped the observation of the two last of these gentle- 

 men ; Dr. Adams being so well qualified to detect it from 

 his observations in Madeira, and Mr. Baker from his ex- 

 pertness in microscopical researches. Dr. Bateman, in the 

 letter above quoted, says, " I have hunted it with a good 

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

 pustules, and in the red streaks or furrows, but always with- 

 out success. 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. Willan in his book speaks of the Acarus as 

 the concomitant of this disease, yet his learned friend just 

 mentioned observes, that he admitted that it was not to be 

 found in ordinary cases, and indeed never seemed to have 

 nlade up his mind upon the subject. When I was at 

 Norwich, in 1812, Dr. Beeve very kindly accompanied me 

 to the House of Industry there, to examine a patient whose 

 body was 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 examin- 

 ation was made in December, in severe weather, when the 

 cold might, perhaps, render the animal torpid, and less easy 

 to be discovered. 



1 I am informed by my learned friend Alexander MacLeay, Esq. late secre- 

 tary to the Linnean Society, that, in the north of Scotland, the insect of the itch 

 is well known, and easily discovered and extracted. 



