DIVISIONS OF THE ANIMAL KINGDOM. XXV 



means of their numerous arms, and myriads of cilia. Many 

 of them are, like plants, fixed to the spot on which they live 

 and perish, as the varied species of Sponge, which are met 

 with on every rocky coast from the equator to the polar seas ; 

 and such are the innumerable Polypi, whose calcareous se- 

 cretions stud the ocean as with bushes and forests, and form 

 new islands and continents of Coral. Many species are ge- 

 latinous, and so transparent as scarcely to be distinguished 

 by the eye from the element in which they live. Yet such 

 creatures have a will, the faculty of motion, and the force to 

 prey on other animals. Such are the Medusae, some large, 

 some microscopic, which float in myriads together, so that 

 the whole ocean seems to be alive with them, giving often a 

 tinge to the waves over many hundred miles, and in the 

 dark emitting sparkles of phosphorescent light. The Radi- 

 ata, passing through almost every conceivable form, from the 

 simple digestive sac, to the sea-urchins, star-fishes, and simi- 

 lar creatures, which we may see studding the submerged 

 margins of our coasts, advance, by insensible gradations, to 

 the groups above them. 



The divisions above the Radiata, are the Mollusca and Ar- 

 ticulata, nearly of an equal rank in the organic scale, but 

 differing from one another in the conformation which they 

 tend to assume. In the Articulata, the nervous system 

 begins to be extended in length, and with this the form 

 of the body. Some of them are minute transparent ani- 

 malcules, invisible to the naked eye ; and some of them are 

 like little wheels, continually revolving, and preying upon 

 the yet feebler creatures with which every drop of water 

 seems filled. A little higher in the scale are the innumer- 

 able parasitic creatures which suck the fluids of other ani- 

 mals, living within their bodies, and frequently proving dan- 

 gerous enemies even to man and the larger animals. Above 

 these are the annulose, or worm-like animals, whose skins 

 are furnished with rings, giving the articulated form typical 

 of the group ; next are the creatures formed with numerous 



