296 A MANUAL OF BACTERIOLOGY 



a size that it rests on the rim and does not touch the bottom. A few 

 drops of water may with advantage be put at the bottom of the 

 glass to keep the egg-white moist. The preparation is kept in a 

 warm place for twenty-four to forty-eight hours and then examined. 

 Antitoxin itself may be used as a culture medium, provided it con- 

 tains no antiseptic (this is now rarely the case). A test-tube is 

 sterilised by heating, or with boiling water or steam from a kettle, 

 antitoxin to the depth of about an inch is poured in, and is coagulated 

 by holding the tube very obliquely in boiling water or steam. After 

 coagulation and cooling the medium is inoculated. If no incubator 

 is available, the culture may be kept in a warm place, or in an 

 inside pocket. 



Many laboratories now undertake the examination of material. 

 Culture outfits are supplied by some, consisting of a sterilised tube 

 containing a sterilised swab. Failing this, a piece of membrane 

 may be forwarded in a tube or bottle which has been sterilised by 

 heating, or with boiling water or steam. If there be no membrane, 

 a swab can be readily extemporised by wrapping a little wool or 

 lint (non-antiseptic] round the end of a piece of wire, knitting 

 needle, hair-pin, penholder, or splinter of wood. The wood may 

 be sterilised by moistening with water and then holding in a flame. 

 Membrane or secretion may also be forwarded on pledgets of wool, 

 pieces of lint or calico, and even on paper, but these are not so 

 suitable. 



(B) In milk. See section on " Milk." 



Vincent's Angina 



An infective malady characterised by sore throat, fetor, 

 dysphagia, and ulceration and membrane simulating diphtheria, 

 The diphtheria bacillus, however, is not present, and the affection 

 is caused by an apparent association of a bacillus and a spirochaete. 

 The bacillus (B. fusiformis) measures 6-8 p. to 10-12 p. in length, 

 has pointed ends and is usually somewhat bent, not straight, often 

 appears feebly motile, and does not stain by Gram. It can be 

 cultivated anaerobically on the ordinary media to which human 

 blood-serum, ascitic or hydrocele fluid has been added. The 

 spirochaete is long and sinuous and very motile, but cannot be 

 cultivated, and is stated to be developed from the fusiform bacillus, 

 Smears may be stained with methylene blue or dilute carbol-fuchsin, 

 and the appearance of the associated organisms is so characteristic 

 that a diagnosis is easily effected (Plate VII. b). 



