50 ANIMAL PAEASITES. 



think it is sufficient to beat the clothes heartily, to brush 

 them in particular places (cuffs, button-holes, and pocket-holes) 

 with soap and water, and sprinkle them with turpentine, which 

 immediately kills the mites. According to Volz the mite can 

 only live one or two days out of the body ; according to others 

 it may live three weeks. How long the eggs retain their power 

 of development out of the body is unknown. 



Shall I say one word upon the retrocession of itch, and the 

 diseases supposed to be produced thereby ? Shall I trace this 

 unlucky theory of the otherwise so meritorious Autenrieth from 

 its origin to the time when Hahnemann and his disciples pub- 

 lished a caricature of these views in their psoradic theories ? 

 The mainstay of this absurdity is now broken, and I pass it over. 

 I may be allowed, however, to mention one case as an example of 

 the mode in which this subject is sometimes treated. Joachim 

 relates : " A girl, eighteen years old, ^vas rubbed with ointment 

 for the itch, and confined in a hot oven for an hour and a half, 

 upon which she became blind. By means of sulphur and deriva- 

 tives applied to the skin, the itch returned again, and the power 

 of sight in five weeks.-" In this case who would not seek the 

 cause of the blindness rather in the heat of the oven than in the 

 retrocession of the itch ? I would not advise Herr Joachim to 

 make the experiment, whether he would not also become blind, 

 after supporting the heat of an oven for an hour and a half, with 

 a healthy body, whether anointed or not ! 



MlTES ACCIDENTALLY TRANSFERRED FROM ANIMALS TO MAN. 



Although a short time ago Bourguignon left the transfer- 

 ability of the mange-mites to man as undecided, we, in Ger- 

 many, have long been convinced, by the thorough-going experi- 

 ments of Hering, Hertwig, and others, that such transfer does 

 take place that passages are actually bored, and itch-like erup- 

 tions produced, in the human skin by these animals. In general, 

 however, these eruptions only last as long as the individual life 

 of the mites transferred. Upon this point, nevertheless, the 

 accounts of observers still vary, some extending the period of its 

 visit to two or three weeks, and others to six weeks and more. 

 It does not appear possible for these animals to pass through 

 their whole development upon the human subject. And if this 

 is the case, I believe it only takes place in those species of mites 



