180 POPULAR HISTORY OF THE AQUARIUM. 



marine Worms ai'e furnished with eyes^ some with tentacukj 

 and the mouth-apparatus is in many species formidable, 

 suited to the carnivorous propensities of the race. Most of us 

 know the three-cornered bite of the Leech; and his brethren 

 of the ocean are not behind in their powers of wounding. 



Coming to characters in which the Annehds differ from 

 each other^ we may notice the general divisions into which 

 they have been cast. 



The Apoda perform locomotion by means of sucking discs, 

 and have no foot-like warts or bristles. 



The CJicBtopoda move by means of bristles placed in 

 bunches on wart-like protuberances. 



Those of the former order are Leeches or leech-like ani- 

 mals, a fine example of which is seen in the Poutohdella, 

 which has a long warty body and a very obvious cup-like 

 sucker at each end. It is marine. 



Those of the latter Order present many interesting pecu- 

 liarities, some of them are among the prettiest objects of 

 the tank. 



Some of the variations are expressed in a homely way by 

 Hugh Miller, in his work entitled ' My Schools and School- 

 masters.' The following passage will be read with plea- 

 sure, for it has about it all the freshness of nature. 



