THE CHARACTERS OF THE DEEP-SEA FAUNA 65 



variety of colour in the deep-sea echmoderms. It is 

 hardly probable that it can be protective or warning in 

 function, and it is difficult to suppose that it is due 

 to any peculiar excretory process. Whether it is due 

 in any way to the influence of the environment, or, 

 like the colour of autumn leaves, to the chemical 

 degeneration of colours that in the shallow-water 

 ancestry were functional, are problems that must be 

 left for the future to decide. 



The colour of the deep-sea Ccelenterates has un- 

 fortunately not been recorded in all cases, but still 

 the few observations that we have, show that in this 

 group, as in the last, almost every tint and shade 

 are represented. 



The colouring of the deep-sea jelly-fishes is said 

 to be usually deep violet or yellowish red. However 

 ( a species of Stomobrachium,' says Agassiz, ' is re- 

 markable for its light carmine colour, a tint hitherto 

 not observed among Acalephs.' 



Moseley records most minutely the colour of some 

 of the deep-sea anemones and corals, and calls atten- 

 tion to the very general presence of madder brown 

 in the soft parts. Agassiz says : ' Among deep-sea 

 Actiniae, a species of a new Cereanthus was of 

 a dark brick-red, while other actinians allied to 



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