i8o 



C.-E. A. WiNSLow AND Anne F. Rogers 



TABLE 14. 

 Correlation between Cell-Grouping and Optimum Temperature for Growth. 



Optimum Temperature 



20° 



20° or 37° 



37° 



Irregular Groups 

 and Chains 



40 



237 

 68 



Packets 



43 

 98 

 14 



A slight but distinct correlation appears between grouping and 

 optimum temperature for growth. In each case most of the cultures 

 grow at 20° or 37° indifferently; but a fair proportion of the more 

 saprophytic sarcinae show better development at 20°, while among 

 the other forms more find an optimum at 37° than at 20°. With 

 regard to the optimum temperature for color formation there is a 

 slight difference, only two-fifths of the sarcinse showing more chromo- 

 genesis at 20° than at 37°, against one- half of the other cultures. 

 This, as we shall see later, is probably connected with a difference 

 in chromogenesis. 



TABLE IS. 

 Correlation between Cell-Grouping and Gelatin Liquefaction. 



Table 15, for the relation of gelatin liquefaction to morphology, 

 shows only that the highest grades of liquefaction are somewhat 

 less numerous among the packets than in the other group. 



The results obtained with regard to the size of the individual 

 cell were much less suggestive than the facts concerning cell-grouping. 

 Dimensions were measured in all cases on the stained specimens, 

 and were recorded independently on at least two occasions. The 

 attempt was made to note in each case the extreme diameters observed, 

 and the values finally adopted represent the average between the 

 recorded extremes. Individual cells ranged from o.i to 2 . o a*-. 

 With the packets it was found impossible to determine the maximum 

 size of the single cell, on account of the frequent occurrence of small, 

 recently formed packets which stained as a whole like one cell. 

 We never felt certain that what appeared like a large cell was not 



