112 CLINICAL BACTERIOLOGY AND HEMATOLOGY 



contain should be examined for this organism as soon as they are 

 opened; the interest in this is chiefly scientific, for opinions are 

 divided as to whether they are caused by this germ or by pyogenic 

 bacteria. In three cases examined by the author it was found (in 

 very scanty numbers) on one occasion, staphylococci on another, 

 and no bacteria of any sort in the third. 



RINGWORM 



An examination of the hair and scales from the skin is 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 information 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 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 micro- 

 scope, using a |-inch lens and a small diaphragm. The spores 

 appear as spherical or oval, highly refractile bodiqs, which can 

 hardly be mistaken for anything but fat globules. This possible 

 source of fallacy may be removed 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. It is a very great advantage to employ some 

 method of staining. These are by no means difficult, though 

 they are somewhat tedious. Two processes, both modifications 

 of Gram's method, will be given. They are not difficult to apply, 

 but are very slow. 



Method of Staining Hairs, Scales, etc. 



Requisites. — i. Aniline gentian violet, carbol gentian violet, or 

 carbol fuchsin. 



2. Gram's iodine solution. 



3. Aniline oil, to which a little strong hydrochloric acid has been 

 added, two or three drops to a quarter of a test-tube full of the 

 oil. Prepare when required, and shake. 



