1 88 CLINICAL BACTERIOLOGY AND ILEMATOLOGY 



it has been demonstrated (see Fig. 30). It is best seen by 

 mounting- a small drop of blood between slide and cover-glass, 

 and examining it in a perfectly fresh state, when the spirilla 

 are easily found from the commotion they cause by pushing 

 aside the red corpuscles. 



11. The gonococcus has been found in the blood in a few 

 cases of ulcerative endocarditis. Its detection by cultural 

 methods is difficult, and the services of a bacteriological expert 

 should be called. We may point out that ulcerative endocar- 

 ditis, septicaemia, etc., supervening in the course of an attack 

 of gonorrhoea, are not necessarily due to the gonococcus. Any 

 pathogenic bacteria . may enter through the lesion of the 

 mucous membrane which the gonococcus has caused. 



12. The B. coll is present in some cases of septicaemia. 



EXAMINATION FOR BACTERIA IN FILMS 



This is the easiest method in which bacteria may be found 

 in the blood, and it does not require such a rigid antiseptic 

 technique as is necessary if cultures are to be taken; but the 

 results, except in a few cases, are much less useful, since it is 

 very rare for most bacteria to occur in the blood in numbers 

 sufficient to render the chance of finding them in films at all 

 promising. It is sufficient (indeed, the only method available) 

 in malaria and relapsing fever, and it may lead to the discovery 

 of the organism in plague, anthrax, and a few other infections; 

 but in general cultural methods should be relied on, and the 

 microscopic examination should be regarded as a mere pre- 

 liminary, enabling the observer to see whether bacteria are 

 present in enormous numbers or not. The films are prepared 

 and fixed in one or other of the methods which will be de- 

 scribed subsequently (see p. 254), and need not be very thin 

 and even. 



The method of staining will depend upon the organism 

 which is likely to be found, and more especially whether it 

 stains by Gram's method. 



If the bacteria which are present in the films do not stain 

 by Gram's method the matter is more difficult, for any stain 

 which colours them will colour the nuclei of the leucocytes 

 also. Jenner's stain may be used, or the film may be stained 

 by eosin and methylene blue separately. The organisms will 



