Chapter III —55— Morphology 



by cytoplasm enclosed in a spore case. When the spore germinates, the 

 chromatin bodies divide, some of the material entering the germ tubes. 

 As the mycelium develops, it becomes filled with granular or rod-shaped 

 chromatin bodies. 



Lachner-Sandoval (247) was the first to recognize, in 1898, the 

 true manner of sporulation among the actinomycetes. This was be- 

 lieved to be a distinguishing character of the organisms. Two types of 

 spores were found to be produced, both asexually, one by the process 

 of fragmentation and the other by the process of segmentation. 



The fragmentation spores were looked upon as analogous to spores 

 formed by true fungi. They are formed by the breaking up of the 

 protoplasm within the cell wall into particles or fragments, more or less 

 uniform in size. These fragments are later liberated by the splitting 

 of the cell wall. During the contraction of the fragments, empty and 

 clearer partitions are formed between them, which have been occa- 



Fig. 12 d (see p. 52). 



sionallv taken for cross walls. When the spores mature, the surface 

 cover becomes less defined and may gradually disappear, as a result of 

 autolysis. The spore-bearing threads thus assume the appearance of 

 chains of cocci, the spores falling apart readily. The surface cover may 

 persist, however, without dissolving, in which case the spores leave 

 through the broken ends of the sporulating hyphae. Sporulation by 

 the fragmentation process begins at the top of the aerial hyphae and 

 proceeds toward the base. This manner of sporulation is characteristic 

 of the genus Streptoviyces. 



Sporulation by segmentation consists in the simple breaking up of 

 the sporulating hyphae by means of cross walls. At first the hyphae 

 are unicellular. At a certain stage of growth, cross walls are formed 

 anid the hvphae break up into small segments. These are cylindrical 

 in form, with sharp edges and are uniform in size, usually 1-2.5 X 

 0.7-0.8iJ.. These often have been considered as true oidiospores (321). 



