* 



Fourth Report to the Royal Society Water Research 



Committee. 



By PERCY F. FRANKLAND. Ph.D., B.Sc., F.R.S., Professor of Chemistry 

 in Mason College, Birmingham, and H. MARSHALL WARD, D.Sc., 

 F.R.S., F.L.S., F.R.H.S., Professor of Botany, Royal Indian 

 Engineering College, Cooper's Hill. Presented to the President 

 and Council, March 14, 1895. 



" On the Biology of Bacillus ramosus (Fraenkel), a Schizo- 

 mycete of the River Thames." By H. MARSHALL WARD, 

 D.Sc., F.R.S., F.L.S., F.R.H.S., Professor of Botany, 

 Cooper's Hill. 



INTRODUCTORY. 



Morphology and Classification. 



During the progress of my investigation of the bacterial flora of 

 the River Thames, I have frequently isolated from the water a 

 schizomycete, which turns out to be in many respects one of the 

 most interesting forms yet met with, and probably one of the most 

 instructive species yet known to science. 



It occurs at all seasons, more or less, but oftenest during the 

 autumn and winter months, and is found on the isolation plates as 

 white colonies, becoming yellowish with age, which rapidly develop 

 into large membranous growths, so like the mycelium of a fine mould 

 that it is quite conceivable, or even probable in some cases, observers 

 might pass it by as a small mucor or other fungus, not belonging 

 to the schizomycetes at all. 



It appears on the plates at all times of the year, though it seems 

 to be commoner in the river water taken in autumn and winter than 

 in the samples of spring and summer. 



It attracted my attention at an early period in the investigation, 

 owing to its rapid growth, the relatively large size of the filaments 

 and cells, and especially the facility with which it can be made to 

 develop spores. Moreover, it presents certain superficial, though not 

 unimportant, resemblances in some of its characters to cultures of 

 Bacillus anthracis, fiom which species, however, it is decidedly dis- 

 tinct, as evinced by its larger size and other pronounced characters. 



VOL. LVIII. U 



