GROUPING. 



37 



when seen in short segments, or when in longer threads 

 are twisted in the form of a corkscrew. (See Fig. 3.) 



FIG. i. 



o 



0$ 



a. Staphylococci. b. Streptococci, c. Diplococci. d. Tetrads, e. Sarcinae. 



FIG. 2. 



d e f 



a. Bacilli in pairs, b. Single bacilli, c and d. Bacilli in threads. 

 e and/. Bacilli of variable morphology. 



FIG. 3. 



-'K/"- 



^N*- 



a 6 c d 



a and d. Spirilla in short segments and longer threads the so-called comma 

 forms and spirals. 6. The forms known as spirochseta. c. The thick spirals 

 sometimes known as vibrios. 



