OF CREATION. 235 



placed edgeways, and projecting one beyond another; 

 others are also tubes, but placed parallel one with an- 

 other on long lines of fragile riband transversely to the 

 direction of the riband (fig. 85). Others, again, are 

 oblong figures united at the edges ; while one group, 

 more complicated than the rest, exhibits numerous 

 projections of the most singular shapes (Xanthidium, 

 fig. 87). 



It cannot but be a matter of great interest to learn, 

 if possible, the use of these minute animals in the 

 economy of nature. That they are not merely acci- 

 dents in creation we may be quite certain, and that 

 they simply enjoy life, and do not contribute to the 

 well-being of the whole, may be considered equally 

 improbable, and too unlike the ordinary course of 

 nature, to be admitted for a moment. All things 

 work together, and we may, in all cases, safely 

 inquire concerning the adaptation of any group, how- 

 ever minute or apparently unimportant it may at 

 first appear. 



It has been ingeniously suggested by Professor 

 Owen that these little creatures are the appointed 

 devourers of organic matter immediately before its 

 final decomposition into inorganic elements. " For 

 consider," says he, " their incredible numbers, their 

 universal distribution, their insatiable voracity, and 

 their invariable presence wherever animal or vege- 

 table matter is undergoing decomposition in water. 

 Surely we must be indebted to them the ever ac- 

 tive and invisible scavengers of the world for the 

 salubrity of our atmosphere ; but they perform a 

 still more important office, perhaps, in preventing 

 the gradual diminution of the present amount of 

 organized matter upon the earth. 



