RINGWORM. Ill 



RINGWORM. 



Examination of the hair and scales from the skin are 

 of very great value to the dermatologist. It settles 

 conclusively the question whether a patient is or is not 

 suffering from ringworm, and often gives important in- 

 formation as to prognosis ; and may enable us to say 

 whether the disease has probably been derived from a 

 human source or has been contracted from one of the 

 lower animals. 



Where the mere diagnosis of ringworm is in question 

 an examination of the hair or scales after soaking in 

 liquor potassae is often sufficient. The materials are 

 placed in a drop of the solution on a slide and covered 

 with a cover-glass ; after a quarter of an hour or so the 

 specimen is carefully examined under the microscope, 

 using a % in. lens and a small diaphragm. The spores 

 appear as spherical or oval highly refractile bodies 

 which can hardly be mistaken for anything but fat 

 globules. This possible source of fallacy may be re- 

 moved by soaking the hair in ether before applying the 

 liquor potassae. 



This is a rapid and simple method, but it does not 

 enable us to diagnose the nature of the fungus with 

 certainty, except in very typical cases, and when spores 

 are scanty they are readily overlooked. It is a very 

 great advantage to employ some method of staining. 

 These are by no means difficult, though they are some- 

 what tedious. Two processes, both modifications of 

 Gram's method, will be given. 



