BACTERIA AND THEIR ALLIES 175 



which had taken the stain freely, as may be seen by Fig. 5, 

 B (X soo). 



At the end of March, 1903, I made another slight variation in 

 the conditions with a small new potato. After careful washing, it 

 was placed in a small tin with a very tightly fitting cover and 

 allowed to soak in ten per cent, formalin for twenty minutes, the 

 fluid having been shaken about several times so as thoroughly to 

 wet the whole internal surface of the tin. The fluid was then 

 poured off, leaving the surfaces wet with the solution as before ; 

 the tin cover was very tightly jammed down and the vessel was 

 placed within a copper incubator at a temperature of 75° F., and 

 allowed to remain there for eight weeks completely cut off from 

 all light. 



When taken out and examined, the cut surface of this potato 

 presented just the same characters as the others ; the whole sub- 

 stance was firm throughout, there was no shrinking, and the central 

 portion was rather darker than the other parts which showed the 

 usual mottling. 



Sections were made, shaken up in distilled water in a small tube 

 as before, and then placed for a short time in a dilute gentian-violet 

 solution. On microscopical examination a large number of the cells 

 scattered throughout the sections were found to show the most 

 delicate branching tufts of what seemed a new kind of microphyte, 

 looking like a species of Cladothrix, which had taken the stain 

 slightly, such as are shown in Fig. 6, B (x 500). These tufts 

 were mostly seen to be sprouting from the internal, or else from the 

 external, surface of the primordial utricle, where it had shrunk 

 away from the cell- wall. At first no Bacteria were found, only 

 tufts of this kind, but a subsequent thorough examination of other 

 sections revealed Bacteria in abundance, and in some cells dense 

 aggregations of them such as are shown in Fig. 6, A (x 500). It 

 seems probable that the tufts are really aggregates of Bacilli grow- 

 ing out from such masses of germ-Uke bodies. In other cells these 

 germ-like bodies were seen originating from the primordial utricle, 

 as shown under a higher power in Fig. 7, A ( x 700), while in 

 B such bodies were to be seen giving rise to filaments which were 

 ramifying over the surface of the membrane. 



A few experiments have also been made with small Turnips about 

 two inches in diameter, to two of which I will now refer. 



A perfectly sound turnip of the size mentioned was, in November, 

 1901, first well washed in water and then allowed to soak in a 



