INFUSORIA. 



301 



little things on colour, set aside the opinion of previous 

 naturalists, that they effected nutrition by "cuticular 

 absorption ';" it also led to a classification, not, as formerly, 

 by shape, but structure. 



The species most frequently observed is the Gonium, or 

 Tablet monad, enclosed in a flat hyaline envelope, irregular 

 in shape, and not larger than the 1 -300th of an inch in 

 length, in which is discovered a happy community of sixteen 

 bright green-coloured cell masses, which at times exhibit 

 a rhythmical contraction and expansion, as in the Volvox. 



Fig. 176. 



1, Gonium pectorale, Breast-plate animalcules. 2, Enchelis, Flask-animaicuies. 

 3, Bergh-mehl, Norway. 4, Vorticella cyanthina, Bell-shaped animalcules. 



They are sometimes called Breast-plate animalcules (fig. 

 176, No. 1). The twenty-four cilia projecting from the 

 sides, and eight from the centre, appear to be actively 

 engaged in satisfying that first law of nature, self-preserva- 

 tion. When they have all attained their growth, the shell 

 divides into four parts, leaving four monads on each ; these 

 four grow in size, and each again divide into four, hence 

 arises their magic number of sixteen ; then, as soon as the 

 sixteen are of a mature size, they divide into a commu- 

 nity of four; and thus go on dividing and subdividing, 

 endlessly fulfilling their appointed destiny in the unbroken 

 links of creation. 



