CULTURAL PROPERTIES 319 



fetal membranes contains the specific bacillus of Bang in enormous 

 numbers. 



Natural Infection. This is brought about by the bull, who spreads 

 the disease from infected to healthy cows. It is also believed that 

 the infection may be spread by contaminated straw, bedding, etc. 



Artificial Inoculation. Pure cultures of the bacillus inoculated into 

 the vagina and intravenously, as practised by Bang, caused abortion 

 in cows and sheep and in a mare. 



Morphology. If a cover-glass preparation is made from the exudate 

 between the uterine mucosa and the fetal membranes very character- 

 istic bacteria are found in great numbers. Many of them are free 

 between cells, many others are found in cells in such masses that the 

 cell bodies are much swollen and extended. These intracellular 

 bacteria are sometimes so dense that the cell itself has become un- 

 recognizable; at other times, however, the nucleus can still be demon- 

 strated. The organisms on first sight appear like cocci, but a more 

 careful exaimnation shows them to be small, short, unequally staining 

 bacilli. Some of them are as large as the tubercle bacillus, others are 

 quite short and coccus-like. The unequal staining depends upon the 

 presence of one, two, or three deeper staining granules. The organism 

 is Gram negative. 



Cultural Properties. Pure cultures of the bacillus can be obtained 

 on a special medium devised by Stribolt, which is prepared as follows : 

 The basis is formed by the ordinary slightly alkaline nutrient bouillon 

 to which f per cent, agar has been added. This medium is then 

 filtered clear and 5 per cent, gelatin is added. The reaction is again 

 corrected, and after a clear product has been obtained it is distributed 

 to test-tubes which are sterilized by the fractional method and finally 

 cooled down to 45 C., when about one-half the quantity of sterile 

 fluid blood serum (also warmed to 45 C.) is added. A tube is then 

 inoculated from the material containing the organisms and dilutions 

 to other tubes, are made in the usual manner. Tube No. 2 is inoculated 

 three times from tube No. 1 with a sterile platinum loop, tube No. 3 in 

 the same manner from tube No. 2, etc. The inoculated tubes are then 

 rapidly cooled in cold water. When tubes so inoculated are kept' in the 

 incubator at blood temperature very small punctiform or sometimes 

 slightly larger round colonies are formed. These are situated about 

 J cm. below the upper surface and extend from 1 to 1.5 cm. down. 

 Thus growth takes place in a very definite zone, but neither above 

 nor below it. The bacillus does not grow in gelatin-agar; it grows 

 very scantily in a 5 per cent, glycerin bouillon, but better in a mixture 

 of two parts of such a glycerin bouillon to which one part of serum 

 has been added. In fluid media a granular sediment is formed after 

 several days. The relation of the bacillus to oxygen is peculiar. It 

 does not grow under strictly anaerobic conditions. It grows better 

 in glycerin bouillon if pure oxygen is conducted through the fluid, and 

 if afterward the opening of the tubes or flasks are sealed air-tight 



