142 



centrally-grouped well-distributed granulations and finely scalloped 

 edge. 



„I 27" is a small light-coloured colony with a very convex 

 surface, round edge, and very granular centre. 



In „I" and „II" the colonies were also small and light-coloured. 

 The edge („I") was slightly undulating. The granulations were rather 

 different. 



In „I 57" two associated colonies are taken. They are large, 

 dark, and flat with rather steep margins and circular outlines. There 

 are a few central granulations. 



In „1" and „II" the colonies were also dark, but they were only 

 of medium size. The border was undulating or scalloped. The 

 granulations varied to some extent. 



„I 5" is a small, very light colony with centrally disposed, 

 but rather widely distributed granulations. The border is uniformly 

 circular. 



In „I" and „II" the colonies were also light, with granulations 

 in the centre. They were of medium size. The edge of ,,I" was 

 round, of „I1" very undulating. 



„H 122" is a small colony and of similar shape to „I 5", but 

 with a small central elevation. A few centrally grouped granulations 

 present. 



In „I" and „II" the colonies were also small. The edges were 

 round and the granulations grouped in the centre, but highly 

 developed. 



„H 151" is quite a small colony with a dark centre and light 

 margin. Mdge circular. Granulations central, rather widely distri- 

 buted. 



In „I" also the colonies were exceptionally small, and dark 

 with centrally placed granulations. The edge however was slightly 

 undulating. „II" was not reported on. 



Of the 10 strains described, H 151 was „atypical", and all the 

 others „typical". 



Besides these 10 strains, about 50 others were examined 

 several times in cultures consisting of isolated colonies. The 

 descriptions furnished give a fairly correct picture of the con- 

 ditions which generally obtained. The first point to emphasize 

 is the great difference that may be present between the Pfeif- 

 fer's bacillus colonies. 



It is naturally important to fully appreciate that it is 

 not sufficient to fix the attention on colonies of a definite 

 appearance, but that the boundaries of the types of colony 

 on the original plates suspected of being Pfeiffer's bacillus 

 are very far apart. 



Moreover the type of colony of the individual strain retains, 



