378 MES. L. J. TELET — CONTKIBUTION TO THE 



no means frequent, and had the periods of observation been less 

 protracted it might easily have been missed. 



The actual process was very rapid, occupying about one minute ; 

 the rod under observation bent and straightened itself alternately 

 about three or four times, with a lashing movement, and then 

 broke at the point of bending (^. e. the second joint from the 

 terminal) and each, part travelled away, generally in opposite 

 directions, viz., going, so to speak, original pole first, and showing 

 at that end the slight " halo " which seemed to point to the 

 existence of flagella. 



'Reactions. — The rods, which may now be definitely called 

 bacteria, stained well with all bacterial stains, notably with Grram, 

 with Heidenhain's iron-hsematoxylin, andwithall the aniline stains.. 



Almost all known stains for flagella, viz., Loeffler's, Yan 

 Ermengem's, Fischer's, Moore's, and very many others, or 

 modifications of these, were applied in the hope of demonstrating 

 the presence of organs o£ locomotion, but though an appearance 

 suggesting either a bunch of flagella, or a single very thick 

 flagellum, at the poles, often resulted, yet the preparations were 

 never sufficiently definite to satisfy me on this point. It is well 

 known that the flagella of certain bacteria (Fischer, 12) may be 

 resistant to all but one particular ingredient in tlie stain, and I 

 have little doubt that the demonstration of these flagella is merely 

 a question o£ some such ingredient which has not yet been hit 

 upon, or of greater technical skill in the operator. Other possible 

 reasons for the failure to demonstrate the flagella may be (1) the 

 extreme delicacy of these organs, which often causes them to be 

 thrown off" in the preliminary process of fixing, or (2) the fact 

 that they may possibly not be permanent structures at all : 

 appearances at times have suggested both, these explanations. 



Life-history of the Bacteria. 

 It still remained to follow out the development of the bacteria, 

 and I was ultimately led to success in this undertaking by a very 

 curious and happy accident which occurred in December 1895^ 

 while the seven Pelomyxai already spoken of were under observation, 

 and therefore it will not be out of place to describe this occurrence 

 at this point, although it is also closely connected with work 

 on the refringent bodies which is to be discussed later. On 

 Dec. 30, 1895, on going to procure the last two of the Pelomyxce 

 from the glass vessel in which they had been placed, no specimens 



