MODE OF MULTIPLICATION 63 



88.3 per cent., albumin 7.6 per cent., ash 3.6 per cent. The 

 dry substance of the bacteria contains the following: albumin 

 65 per cent., ash 31 per cent. From 76 to 80 per cent, of 

 the ash consists of sodium chloride and phosphate. 



Morphology of Bacteria. — For the purposes of this book it 

 will suffice to classify the bacteria roughly into three mor- 

 phological groups with their subdivisions, the members of 

 each group being identified by their individual outline, viz., 

 that of a sphere, a rod, or a spiral. To these three grand 



Fig. 2 



oo. 



00000° 



CD 



00 % < 





a, staphylococci; 6, streptococci; t, diplooocci; d, tetrads; e, saroinee. 



divisions are given the names cocci or micrococci, bacilli, 

 and spirilla. 



Mode of Multiplication. — In the group micrococci belong 

 all spherical forms — i. e., all those forms the isolated indivi- 

 dual members of which are practically of the same diameter 

 in all directions. (See Fig. 2, a, b, c, d, e.) 



The bacilli comprise all oval or rod-formed bacteria. (See 

 Fig. 3.) 



To the spirilla belong the bacteria that are curved when 



