156 



SULPHUR BACTERIA 

 Methods of Reproduction. 



(A) Fission. — The normal method of division is by simple 

 fission. In normal cultures uni- and diplo-cocci preponderate, 



Fig. 35. — Thioporphyya volutans (El'is). 



Stages in bud development — ■ 



a. — First stage. Formation of a peripherally placed clear region from which 



the bud develops. 

 b. — Second stage. Protrusion of the bud. 

 c. — Third stage. Still further protrusion of the bud. Each contains a 



single sulphur globule. The bud has no external covering, and 



assumes a wavy outline when treated at this stage with staining 



reagents. 

 d. — Fourth stage. Separation of the bud from the parent cell. Still 



shows a wavy outline when stained. 

 e. — Fifth stage. The completed bud. Remains spherical when stained so 



that probably a resistant covering is formed at this stage. 



