THE C(ELENTERATES 155 



up a position on the same portion of the shell, and that, when fully 

 expanded, its mouth is usually turned towards that of the crab. 

 This seems to be a very favourable position for the anemone, since 

 it is one that will enable it to catch the waste morsels from the 

 crab's jaws by its expanded tentacles. But it is, perhaps, not so 

 easy to suggest a means by which the anemone can make an 

 adequate return for free board thus obtained. It is well to re- 

 member, however, that crabs are regarded as such delicate morsels 

 by fishes that we have already spoken of the value of these 

 crustaceans as bait ; while the fact that sea anemones remain 

 perfectly unmolested in rock pools inhabited by most voracious 

 fishes, coupled with the fisherman's experience as to the absolute 

 worthlessness of anemones as bait, is sufficient in itself to justify 

 the conclusion that these creatures are very distasteful to fishes. 

 This being the case, it is possible that the hermit crab is amply 

 repaid by the anemone for its liberal board not only by partially 

 hiding the crab from the view of its enemies, and thereby rendering 

 it less conspicuous, but also by associating its own distasteful 

 substance with that which would otherwise be eagerly devoured. 



"When the hermit grows too large to live comfortably in its 

 shell, a change of home becomes necessary, and it is interesting 

 to observe that the anemone living on the outside of the shell 

 transfers itself at the same time ; and this is a matter of vital 

 importance to the crab, since it usually changes its lodging at the 

 moulting period, at which time its body is covered by a soft skin, 

 and is then even more acceptable as prey to the fishes. Thus the 

 anemone accompanies its host, affording it continued protection 

 during the period of its greatest danger. 



Before leaving the ccelenterates we must refer to one other form 

 which, though not often having its habitat between the tide-marks, 

 is nevertheless a very common object in the neighbourhood of 

 fishing villages, where the refuse from the nets used in deep 

 water has been thrown on the beach. We refer to the peculiar 

 animal known to fishermen as ' Dead Men's Fingers,' and to the 

 naturalist as the Alcyonium. 



When seen out of water it is not by any means an inviting 

 object, but is apparently a mass of gristly matter, of a dirty 

 yellowish or brownish colour, sometimes flattened and shapeless, 

 and sometimes lobed in such a manner as to suggest the popular 

 name so commonly applied. It is always attached to some hard 

 object, such as a stone or a shell, and is so frequently associated 



