160 DROPS OE WATER. 



is found principally among duckweed, and is 

 pretty numerous in spring and summer. 



Metopidia lepadella greatly resembles the 

 genus Lepadella mentioned before, being flat, 

 oval, and having a forked foot, but it has two 

 red eyes. It is very transparent, particularly 

 the sides ; is lively, and not uncommon. 



The Slephanops lamellaris is a very pretty 

 creature, and is easily known by its head having 

 a kind of hood extended over it, which is trans- 

 parent, and cannot be withdrawn within the 

 lorica, but probably serves as a defence to the 

 delicate cilia. Its swift movement renders it 

 difficult to observe ; and before I had seen the 

 little creature actually withdraw its cilia, I 

 imagined the hood was an appearance only, 



