10 i PROCEEDINGS OF THE AMERICAN ACADExMY 



The other portion of the kephlr-graiu is made up of Bacteria em- 

 bedded iu a zoogloea mass which is firm and ehistic, comprising the 

 bulk of the grain. The individual cells are short, cylindrical, and 

 rod-shaped, 3.2 /x to 8 /j. long and 0.8 yu. broad, with homogeneous pro- 

 toplasm. These cells increase by the regular splitting process charac- 

 teristic of Schizomycetes. 



The Bacteria ia the zoogloea are motionless ; but in addition to 

 these, when the kephir grain is placed in a nutrient solution, there are 

 to be seen moving cells, exactly like the motionless ones in both 

 form and size. By allowing these moving cells to dry upon a slide, 

 then staining with Extract Campech. and removing the excess of the 

 stain, Kern was able to demonstrate a very thin thread-like wavy 

 cilium on but one of the ends of each cell. 



Exposed to unfavorable conditions the Bacteria cells grow out into 

 Leptothrix threads, varying from 10 yx to 40 /a in length, which are 

 merely the necessary consequences of successive cell-division in which 

 the products do not separate from each other. At various intervals 

 in the length of such a thread agglomerations of protoplasm occur. 

 At first there is hardly an indication of the splitting of such a mass, 

 there being merely tiny incisions on either side ; but these become 

 larger and larger, until finally a single protoplasmic mass has given 

 rise to two spores, separated by a regular ceK wall. Thus it happens 

 that in a Leptothrix thread each cell has tw( spores situated one at 

 either end. Kern mentions still another kind of spore formation, seen 

 in the individual cells, which differs markedly frum that just described. 

 In these cells spore formation begins with the appearance of a small 

 bright point at each end of the cell. The points enlarge more and 

 more, assume a well defined contour, and uliimately become true 

 spores. The form is always round, the diameter never exceeding 

 that of the mother cell before they are freed, but reaching 1 yu, after 

 liberation. 



Kern names his kephir Bacterium Dispora Caiicasica, uov. gen. et 

 nov. sp., with the following distinguishing characteristics: — 



(1.) The vegetative cells are in the form of short cylindrical rods, 

 3.2 /A to 8 /A long, and 0.8 /j. broad. 



(2.) In the zoiigloca condition the cells form white elastic clumps 

 of considerable size. 



(3.) The moving vegetative cells liave on one end a thin, thread- 

 like, wavy cilium. 



(4.) The spores are round ; when in the cells their diameter never 

 exceeds that of the mother cell ; when free, they may reach 1 yu, in 

 diameter. 



