XIII.] 



SPIROBACTERIUM. 



123 



2. Pigment spirilla. 



(a) I have seen on paste a spirillum, morphologically identical 

 with spirillum undula ; it is of a pale pink or rosy colour. 1 

 It is motile, and forms a kind of zooglcea, the individuals being 

 closely placed and therefore producing a rosy colour of a more 



f ~ 



'niiaf t : 





. IG 97 .BLOOD OF RELAPSING FEVER (HUMAN). 



Blood-corpuscles and spirilla Obernieyeri. 

 Magnifying power 700. (After Koch.) 



decided tint. Where they form continuous masses, the naked 

 eye can detect the rosy tint. 



(b) Spirillum sanguineum (Ophidomonas sanguined Ehren- 

 berg). This was observed by Cohn and Warming 2 in pond- 

 water. Morphologically it is identical with spirillum volutane. 



1 " On a Rose-coloured Spirillum," Quar. Journ. of After. Scj., vol. xv. New 

 BeriM. 



2 Leitr. z. Biol. d. Pflanzen, vol.1. 



