136 BACTERIOLOGICAL DIAGNOSIS. 



When the abscess has been opened a considerable 

 quantity of pus should be allowed to flow out, and the 

 sterilised pipette is then to be passed through the 

 incision (care being taken to avoid contact with its 

 sides) and the pus carefully sucked up into the bulb. 

 The fluid thus obtained may be used to inoculate 

 cultures there and then, or both ends of the pipette 

 may be sealed in the flame and the pipette sent to a 

 laboratory. 



THE EXAMINATION OF Pus. 



The organisms which may cause pus are extremely 

 numerous, the most important being streptococci, 

 staphylococci, the pneumococcus and the gonococcus, 

 the bacilli of typhoid fever, tuberculosis, and glanders, 

 the bacillus coli communis, the bacillus pyocyaneus 

 (the organism which produces blue pus^i, and the fungus 

 of actinomycosis. In the majority of cases the organism 

 which is present in a given sample of pus can be 

 determined by a microscopic examination of films 

 prepared in the usual way and stained by a simple 

 stain, such as carbol-thionin. A specimen should also 

 be stained by Gram's method and the results compared. 



When cultural examinations are required they had 

 better be carried out in a public laboratory. If the 

 practitioner should desire to carry them out for himself 

 he had better make stroke cultivations on agar in the 

 manner described on page 22, and incubate them for 

 twenty-four hours at the temperature of the body. The 

 appearances of the colonies will be similar to those 

 described as occurring in cultures made from the blood, 

 to which the reader is referred. It is to be noted, 

 however, that the gonococcus will not grow under 



