Report on the Bacteriology of Water. 



303 



At 9.45 another segment, also a terminal one, was selected for 

 observation, and behaved as follows : 



Here, again, the extraordinarily irregular growth comes out clearly, 

 looking as if the segment, having gradually slowed down its rate of 

 growth to a minimum from 9.45 to 10.20, suddenly began to grow at 

 a rapid rate again. 



The following measurements were made on a terminal segment, of 

 the same culture, measuring 18'2 yit, and showing one distinct septum 

 only, though each cell was almost certainly divided by a median 

 septum during the period. * 



At the end of the period I assured myself that the segment contained 

 one very distinct septum dividing it into two parts, or secondary 

 segments; the apical one measuring not quite 11 ft (my numbers 

 give 10'92), and the other a little over 9 ft (9' 10), and each of these 

 had an extremely faint median septum in it. According to this, the 

 segment 20 /* long consisted of four cells each, more or less, 5 /t long, 

 and we must infer that they were growing at slightly different rates 

 part of the time. 



Another terminal segment of the same culture was watched under 

 the l/12th immersion. It measured 62'88 ft at 12.7 (P.M.) and consisted 

 of eight visible cells, and probably each of these with a septum. As 

 near as I could measure, the primary septa, which were very distinct, 

 stood as follows: One (which I will call A) stood at 30'03 /t from tlu; 

 apex, dividing the whole segment selected into a (fig. 28) distal 

 (apical) moiety measuring almost exactly 30 /t, and a proximal 



