142 



SULPHUR BACTERIA 



P 



'^f •s:% ..vi 



#. 







.J*' -^^ 





b 



Fig. 27. — Chvomatium Okenii (Ehrenberg). 

 «.— Photomicrograph of Chv. Okenii, showing the inchisions of sulphur 



grains, x 200. 

 6.— Another photomicrograph, one organism, showing the single large 



compound cilium. x 500. 

 c— Diagrammatic representation of one of the cells, showing sulphur 



granules, each showing as a thick black ring with a clear centre. X 1 6,000. 



