G. S. Graham-Smith 
51 
single threads projecting from the loops are of common occurrence. 
Segmentation of the threads forming the processes ultimately occurs 
(Fig. 5) and indications of the original loops are lost. At this stage the 
positions of the original loops are marked by bands of parallel bacilli 
often disposed at right angles to the axis of the process (Fig. 6). If 
the condition of the agar permits very rapid lateral growth from such 
processes often occurs at this time. 
Diagram 14. Illustrating certain irregular modes of development in an 
organism of the subtilis group on the surface of agar. 
On thick agar a film is produced by the union of such processes 
and their lateral projections. During its production many beautiful 
and fantastic designs may be seen. 
Hutchinson (1906, p. 130) illustrates the growth during four hours of 
a thread-forming organism, B. lactis ctlbus, apparently belonging to the 
4—2 
