56 Synopsis of the Bacteria and Yeast Fungi. 



A Fungus which is often very troublesome, because it defiles the 

 water and stops up the narrower pipes. The cylindrical threads, some- 

 what clavate above, are visibly articulated ; the joints afterwards 

 separate from one another, but are then surrounded by a sheath, which, 

 originally colourless, becomes of a yellow or yellowish-brown colour by 

 impregnation with iron. The sheath, at first closed, is burst at last 

 by the continually dividing joints, which then escape. Each joint can 

 develop a new thread. In other cases, however, the thread remains 

 enclosed in the sheath ; its joints are divided by closely contiguous 

 transverse partitions into flat discs, which then break up by vertical 

 partitions into smaller roundish cells : the latter may be designated the 

 spores of the Fungus. They often develop, even while still within the 

 sheath, into new threads, which grow through the gelatinous swollen 

 sheath ; or else they leave the sheath, and undergo further develop- 

 ment outside it. They either grow into threads, or form by repeated 

 bipartition larger or smaller colonies of roundish cells, held together 

 by their membranes, which assume a gelatinous consistence. These 

 colonies are designated the Palmella form (probably the Palmellina 

 flocculosa of Radlkofer) ; each of their cells can again form a thread. 



[According to Eyferth, Bot. Zeitung, xxxviii. 673, C. Kuhniana 

 is identical with Sph&rotilus natans. A. Giard, Revue Internal, des 

 Sciences, x. 190, in describing the infection of the drinking water of 

 Lille, in 1882, by this Fungus, says that the " microgonidia," which 

 are formed by transverse division of the clavate ends of the tubes, 

 exhibit for some time an active movement, and with a high power 

 (Hartnack, No. 12, immersion) he saw the flagellum. A full account 

 of this Fungus will be found in Quart. Jour. Micr. Set., 1873, P- l &3- 



