IXFUSORIA. 



447 



TnP.EE-BIDED EUGLESA. 



it rolls irregularly over and over in all directions, not 

 revolving on its long axis, and thus giving you very 



satisfactory views — though only 

 momentary — of the keel with 

 which the back is furnished. It 

 is in the tui-nings of such niinntc 

 creatures that tlie microscopist 

 often gets a glimpse of peculiari- 

 ties of form, which a view of the 

 animal Mhen in repose, however 

 long continued, fails to reveal. Longitudinal interrupted 

 lines are seen running down the body of this pretty leaf, 

 which do not appear to mark irregularities of the sur- 

 face, and therefore are probably internal. Eiirenberg 

 calls these and similar collections of grannies " ova," 

 or eggs ; but this is to cut the knot, instead of untying 

 it. There is no sufficient reason to believe that these 

 animals increase by ova. 



About the front of all these Euglence^ yon may 

 discern now and then a slight flickering or quivering 

 in the water. The power we are using, though best 

 for the gen.eral display of the form, is insufficient to 

 resolve this appearance : I will put on a higher objec- 

 tive. You now see that there proceeds from the frontal 

 part of the body, along and very slender filament, which 

 is whisked about in the manner of a whip-lash. This 

 is considered to be the organ of locomotion ; but I 

 rather doubt that such is the function ; the smooth and 

 even gliding, often rotating, of the creature, seems more 

 like that produced by minute and generally distributed 

 cilise, than that caused by the lashings of a single long 

 thread. 



Yet two more species of this extensive genus we 



