GERMINATION. 53 



spiral forms. Efforts toward their cultivation under 

 artificial conditions have thus far been successful in 

 only a comparatively limited number of cases. Mor- 

 phologically, they are thread- or rod-like bodies 'which 

 are twisted into the form of spirals. In some of them 

 the turns of the spiral are long, in others quite short. 

 In some the threads appear rigid, in others flexible. 

 They are motile and multiply apparently by the simple 

 process of fission.^ In most respects, save form and the 

 property of producing spores, they are analogous in 

 their mode of growth to the bacilli. 



The micrococci multij^ly by simple fission. When 

 development is in progress a single cell will be seen to 

 elongate slightly in one of its diameters. Over tiie 

 centre of the long axis thus formed will appear a slight 

 indentation in the outer envelope of the cell ; this inden- 

 tation will increase in extent until there exist eventually 

 two individuals which are distinctly spherical, as w'&s 

 the parent from which they sprang, or they will remain 

 together for a time as diplococci ; the surfaces now in 

 juxtaposition are flattened against one another, and not 

 infrequently a fine, pale dividing-line may be seen 

 between the two cells. (See Fig. 2, c and d.) A similar 

 division in the other direction will now result in the 

 formation of groups of fours as tetrads. 



In the formation of staphylococci such division occurs 

 irregularly in all directions, resulting in the production 

 of the clusters in which these organisms are commonly 

 seen. (See Fig. 2, a.) With the streptococci, however, 

 the tendency is for the segmentation to continue in one 

 direction only, resulting in the production of long chains 

 of 4, 8, and 12 individuals. (See Fig. 2, h.) 

 1 Dividing into two transversely. 



