SPIROCH^ETES : MULTIPLICATION 69 



throughout as a duplicated row of dots with the un- 

 staining portions as tags to them. The body proto- 

 plasm now concentrates around the dots, and a 

 relatively clear, central area is produced. A split in 

 the body begins at one end, and the two limbs so 

 formed begin to move rapidly. Their vigorous lash- 

 ing extends the slit, and finally the two newly 

 formed organisms lie in a straight line, and by 

 moving in opposite directions effect the final separa- 

 tion. As the halves of the parent spirochaete 

 separate, so the tags on which the bars of nuclear 

 material rest join up, forming a new zigzag skein, 

 along which the granules gradually spread out to form 

 new bars. The chromatin during the intermediate 

 portion of the division period shows a series of well- 

 marked spiral lines. We would again emphasize that 

 all these features can be seen in life by using the 

 paraboloid condenser, and that the division has been 

 followed from beginning to end. 



Transverse division also occurs. In this case a 

 spirochaete begins to elongate, and as it does so, a 

 series of ripples or waves pass along the body of the 

 organism from each end, a neutral zone being thus 

 created where the two waves meet. Return waves 

 of less intensity then pass from the central node out- 

 wards to the ends, die out, and are succeeded by a 

 new series, which neutralize one another at the 

 same point as previously. The number of waves 

 increases in frequency, and the time of each wave is 

 correspondingly shorter. Great strain is thus brought 

 to bear on the spot referred to as the central node, 

 and a perceptible thinning of the organism occurs 



