THE MICROSCOPE. 



35 



& Co., publishers of Dr. Piffard's admirable 

 work, ** Diseases of the Skin." By this ad- 

 justment the patient can be examined in any 

 posture, standing, rechning, or sitting, with 

 much accuracy and ease. By these low pow- 

 ers cases of alopecia can be well studied. In 

 certain stages of either eczema or psoriasis 

 a differential diagnosis is well nigh impossible 

 by natural vision, while with the lens the 

 case becomes quite simple, points in diagnosis 

 being clearly observed. 



Acne is sometimes confused with sec- 

 ondary tubercles. Acne has its papular stage. 

 Acne is usually preceded by comedo, and is 

 always on the site of a sebaceous follicle^ 

 either of the first or second class, which can 

 be readily observed by a double convex lens. 



These cases are full of annoyance and concern for both patient 

 and friend. With a clear diagnosis one can treat successfully those 

 lesions amenable to our art by aid of the valuable treatises of Amer- 

 ican Dermatologists. I say American, because I believe we have 

 produced the best authors and practitioners in this specialty. 



So much for examinations of lesions themselves. On the other 

 hand we have to meet many lesions which are but in the order of 

 sequence the cause being only discernible in some cases by micros- 

 copic aid and with those for the most part this paper is to deal. 



These diseases are in general Morbii Cutis Parasitica. The 

 parasite being either; i, Animal, or ii, Vegetable. 



Of the animal parasites but slight mention need be made as 

 the parasite is readily detecLed by ths naked eye if carefulness is 

 used in the search. The Itch mite is m )re difficult to discover but 

 is readily found by the microscope. The lesions also are quite 

 characteristic ; for instance : 



i I, Capitis. 

 Pediculus-^ ii, Corporis, 

 (ill, Cruris. 

 Scabies. Dr. Bononio was among tlie first to detect the parasitic 

 character of the disease known as the itch. On turning one out of 

 the pustules from between the fingers with the points of very fine 

 needles under the microscope a minute animal was discovered very 



