412 EVENINGS AT THE MICEOSCOPE. 



cilia; the mouth, which is a long opening on the front 

 part, and at the left side (as to the animal) of the ventral 

 surface, is fringed with long cilia, which are continually 

 vibrating. These are the organs of the darting motion ; 

 but the creature crawls like a mouse, along the stems of 

 conferva, &c., which it performs by means of curved spines, 

 called uncini, near the front part, the points of which are 

 applied to the stem, and also by long stiff styles or bristles, 

 which project backward and downward from the hinder 

 part. Sometimes the animalcules crawl for a moment 

 back-downward, on the inner surface of the glass cover, 

 when the bases of the anterior curved spines appear 

 dilated like large spots. The spines are not capable of 

 much action, but they are rapidly used. The general 

 appearance of the creature reminds us of the little Wood- 

 louse or Armadillo of our gardens. The interior of the 

 body is occupied with a granular substance, in which are 

 scattered many globular vesicles of different sizes. The 

 animal is very transparent, and almost colourless. They 

 increase very fast by transverse division, which is per- 

 formed under the microscope, so as greatly to increase the 

 number under examination, even in an hour or two. A 

 constriction forms in the middle of one, which quickly 

 deepens, dividing the oblong creature into two of circular 

 figure. The mouth of the new one, with its vibratile cilia, 

 is formed long before separation is complete, and at the 

 same end and side as in the parent. The styles and bris- 

 tles then form, and the creatures are held together for a 

 few seconds by these organs, even when the bodies are 

 distinctly severed. When separated, they retain the 

 round form for some time. 



When a drop of such water is examined between two 

 plates of glass, it is amusing to observe the numbers that 

 congregate in the little pools left by the gradual drying of 

 the fluid. This probably becomes unfit for respiration ; 

 for the motion of the cilia becomes more and more languid, 



