CHAP. XI CULTIVATION OF THE BACILLUS 93 



such 'cultivations on incubation is still very consider- 

 able. But if on exactly the same lines plate cultiva- 

 tions or slanting gelatine tube cultivations be made of 

 the blood of a fowl dead of fowl enteritis, the number 

 of colonies is extremely limited, — some tubes remain 

 free of colonies, others contain only a very limited 

 number. 



The number of colonies that make their appear- 

 ance when using a small particle of the spleen tissue 

 in fowl enteritis is, as might be expected from what 

 has been said in the preceding chapter, considerably 

 greater than when using the heart's blood. The 

 character of the colonies and the rate of growth are 

 different in the two diseases. In the case of the fowl 

 enteritis, the first signs of the colonies are noticed 

 with a glass very distinctly after 24 hours' growth as 

 greyish translucent dots. During the second and 

 third days the colonies situated on the surface rapidly 

 enlarge into greyish -white translucent discs with 

 thinner angular margin ; they remain small spherical 

 dots when situated in the depth. In transmitted 

 light the superficial as well as the deep colonies are 

 brownish, the latter of course more so than the former. 

 The superficial colonies grow steadily in breadth, be- 

 come more angular, are large and thin as compared 

 with those of fowl cholera (Fig. 45), and do not at any 

 time look yellowish-white like the latter. The chief 



