332 THE MICROSCOPE. 



extremity, and presenting at the opposite end a distinct 

 mouth. Within this young animal, whilst still inclosed in 

 the body of its parent, we see a distinct nucleus, and the 

 usual contractile space of the full grown creature. When 

 mature, the offspring tears its way through the membranes 

 inclosing the Acineta, which, however, immediately close 

 again. The latter continues protruding and retracting its 

 filaments, and soon produces in its interior a new nucleus, 

 which in its turn becomes metamorphosed into a young 

 Vorticella. 



The same faculty of inclosing themselves in a cyst is 

 said to be made use of by the Vorticella, as a means of 

 self-preservation if the water in which they have been 

 living dries up. When the animal is thus encased, the 

 mud at the bottom of the pool may be baked quite hard 

 in the sun without doing it the least injury ; and in this 

 state the creatures are often taken up by the wind with 

 the dust which it raises from the surface of the parched 

 ground, and borne along to great distances, so as to 

 cause their appearance in most unexpected localities (they 

 are frequently found in roof gutters), where the first 

 shower of rain calls them back to active life. These pro- 

 cesses, or changes, may be looked for in several of the 

 allied genera with so little variation, as far as observations 

 have hitherto shown, that it will be unnecessary to allude 

 to them more particularly. 



Vorticella cyanthina, fig. 176, No. 4, has a fringe of cilia 

 surrounding the margin of its cup. A single animal is 

 first seen, which increases, and then divides into two 

 perfect animals, joined by a stem. 



The Stentor, " Trumpet animalcule," belongs to this fa- 

 mily, fig. 185, No. 4. The body is of a trumpet-shape, and 

 of various colours white, blue, yellow, red, and green. 

 They swim in a parallel line to their sides, sometimes tail 

 first, rotating on their own axis ; and attach themselves 

 to objects by a sucker at the lower part. Some have 

 cilia covering their bodies, and a long fringe over their 

 gaping mouths, which is characteristic of their ravenous 

 nature. The prey may be seen in their interior, as if 

 strung like a string of beads ; they differ from many 

 gluttons by possessing great activity, and moving swiftly 



