386 THE BEGINNINGS OF LIFE. 



M. Nicolet states that this form, resembling Dujar- 

 din's Trichomonas 'vaginalis^ speedily passes on to the 

 development of an Amoeba, resembling that which was 

 named after Gleichen by Bory de Saint Vincent. After 

 its escape from the globule in which it was formed, it 

 swims about for a time with the aid of its vibratile 

 cilia, then fixes itself by means of its caudal filament, 

 either to the surface of the plant or to the walls of the 

 vessel in which it is preserved, where it continues to 

 oscillate, owing to the continuous agitation of its cilia. 

 It soon begins to project amcsboid expansions, which 

 are generally long and simple, though after two or 

 three days it detaches itself from its pedicle, and swims 

 about for a time before again coming to a state of 

 rest. ' Its body then becomes quite spherical, whilst it 

 loses its locomotory cilia, and becomes bristled with 

 straight and slender rays, which give it the appearance 

 of an Actlnophrys.^ This new form {m) often lasts less 

 than a day. ^ The rays then disappear by retraction, the 

 body flattens itself, becomes discoid, and soon protrudes 

 new expansions on all sides, though these are larger, less 

 regular, and resemble those of ArcelU. Shortly after- 

 wards the disc extends itself on one side into rounded 

 lobes, and an Amoeba is formed. For a time the more 

 granular substance, in which the vacuoles form, remains 

 agglomerated posteriorly; though later, the granules 

 diflFuse themselves throughout the whole mass, and then 

 this Amoeba, named after Gleichen, has no longer any 

 characters by which to distinguish it from other Amcebig.' 



