MATERIAL FOR EXAMINATION IN DISEASE. 241 



able of the culture media to the bedside or autopsy table. 

 Such a list of media, if fairly complete, would comprise 

 nutrient bouillon alone and mixed with one-third its 

 quantity of ascitic fluid, slanted nutrient agar, and 

 firmly solidified slanted blood -serum. If only one 

 variety of media is to be used the solidified blood- 

 serum is most useful for parasitic bacteria, and this can 

 be easily carried by the physician and inoculated by 

 him, even if he is not very familiar with bacterio- 

 logical technique. The material must be obtained in 

 different ways, according to the nature of the infection. 

 For the detection of the bacteria causing septicsernia 

 we are met with the difficulty that there are apt to be 

 very few or no organisms present in the blood until 

 shortly before death. It will, therefore, be useless to 

 take only a drop of blood for cultures, as even when 

 present there may not be more than eight or ten organ- 

 isms in a cubic centimetre. If cultures are to be made 

 at all, it is, therefore, best to make them correctly by 

 taking from 3 to 5 c.c. of blood by means of a sterile 

 hypodermatic needle, or a suitable glass tube armed 

 with a hypodermatic needle, from the vein of the arm, 

 after proper cleansing of the skin and a tiny incision. 

 Into each of five different tubes containing bouillon we 

 add one-fifth of the quantity of blood withdrawn. We 

 have made by this mixture of blood and bouillon a most 

 suitable medium for the growth of all bacteria which 

 produce septicaemia, and at the same time have added a 

 sufficient quantity of blood to insure us the best possible 

 chance of having added some of the bacteria producing 

 the disease. We also streak several nutrient agar plates 

 with blood, so as to indicate roughly the number of 

 organisms present, if they happen to be in abundance, 



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