PROTRACTILE MOUTHS 



understand why they are sometimes called sea-anemones, 

 sometimes " sea-roses ". The beauty of their brilliant 

 colours, and the appearance of their tentacles like flower- 

 petals, justify these poetic names. But when we touch 

 and handle them, we may understand also the reason 

 for another name which is not so flattering, that of" sea- 

 nettles ", which is justified by the sensation of burning 

 which may be felt when they are touched. These supple 

 tentacles, sometimes the body itself, have in them a 

 stinging apparatus which comes into play when the 

 animal is touched. 



The sea-anemones eat only occasionally. It is only by 

 chance that food comes their way. It may take the form 

 of some animal, a little fish for example, which swims 

 within reach of their tentacles and finds itself captured. 

 Then the tentacles all tighten round the victim, coming 

 together about it like an envelope. They convey it to 

 the mouth which opens wide to receive it, and so it passes 

 to the cavity of the stomach, where digestion takes place 

 gradually as the victim is brought into it by degrees. 

 In this animal such a meal is a rare, an accidental, 

 happening. Most often it must go without. Days 

 and weeks pass without any victim presenting itself. I 

 have known sea-anemones to live for several months in 

 an unused tank without eating anything. The slight 

 amount of nutriment provided by the water, which was 

 always being renewed, was sufficient for them. They 

 display, in a more striking manner than we see else- 

 where, the remarkable power of resistance to hunger 

 which all aquatic animals possess, fishes among them. 

 Fish can survive for weeks without feeding; their own 

 substance serves them as food, and they keep themselves 

 alive though they grow thin and emaciated. The 

 water maintains, if it does not nourish. In the world 

 of waters there is a certain element of truth in the 

 expression " living on hardships " which is so untrue 

 so far as land-dwellers are concerned. 



This infinitesimal kind of meal, supplied by the water 

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