BACTERIOLOGICAL EXAMINATION OF MOUTH AND FAUCES 155 



thicker, and when removed leaves an ulcerating or bleeding- 

 surface, but the ulceration is less than in the other form. The 

 disease runs a shorter course, recovery occurring in four to 

 eight days. This is the form which so closely resembles diph- 

 theria, and which, I have no doubt, has often been mistaken 

 for it, even after a superficial bacteriological examination of 

 the membrane. 



The diagnosis is made from films prepared from the swabs, 

 stained by Gram's method and counterstained by carbol 

 fuchsin. In the m'ore common form (the ulcero-mem- 

 branous) two very interesting organisms will be found a 

 bacillus and a spirillum (Plate IV., Fig. 2).* In the diph- 

 theroid form the bacillus is present, but the spirillum is absent, 

 or present in comparatively small numbers. In either form of 

 the disease the characteristic organism or organisms may be 

 associated with streptococci, staphylococci, etc., and these 

 secondary infections may give rise to grave complications. 



The B. fusiformis, which occurs in both forms of the disease, 

 may be found, in small numbers, as a normal inhabitant of 

 the mouth, and occurs in myriads in the disease. It varies in 

 size, but is on the whole a large bacillus, about as long as the 

 diameter of a red blood-corpuscle, or even longer. Typically 

 it has both ends pointed, giving it the shape of a greatly 

 elongated spindle, but other forms always occur, and may 

 even constitute the majority of the bacilli present. It often 

 contains two or three clear vacuoles, which may not be noticed 

 if the staining is too deep. Both the bacillus and the spirillum 

 are usually actively motile, and it is a good plan to check the 

 results of the examination of the stained films by mounting a 

 fresh wet specimen between slide and cover-glass, and examin- 

 ing it under the oil-immersion lens. 



The B. fusiformis plays a very important part in many in- 

 flammatory and ulcerative conditions in and about the mouth 

 and adjacent cavities, the teeth, etc. For instance, in associa- 

 tion with the same spirillum it is present in the pus of pyor- 

 rhoea alveolaris. The lesions it causes are all associated with 

 a foetid odour, and the cultures (which are very difficult to 

 obtain) have a similar smell. 



The spirillum occurs chiefly in the ulcero-membranous form, 



* It is possible that these are different stages of the same organism, a 

 protozoon. 



