Coloration of Marine Animals. 225 
colours of anemones act as a warning is not borne out by the 
eagerness with which the cod swallows the brightest, such as 
Stomphia, while the smaller flatfishes fill their stomachs with 
Edwardsie. 
‘Thus it would appear that mechanical protection is mostly 
subserved by the bag of small anemones around the caudal 
extremity of the Indian hermit-crab, Chlenopagurus Ander- 
sont. 
The red of Tubipora and the coral of commerce, the varied 
tints of coral polyps, in which green of many shades predomi- 
nates, the blue of /eliopora, the purple of Pennatula, the 
reddish or pink colour of Tubularia, Coryne, and Syncoryne, 
and the long chain of reddish-orange polypites of Diphyes as 
it darts hither and thither amongst the bluish masses of 
floating oceanic animals with much greater speed and certainty 
of direction than usually shown by them, and even seems to 
elude the hand-net or the dipping-bottle, appears to have as 
little to do with protection or warning as the green of 
Lhizosolenia or the red of the wild poppy. Nor does sexual 
selection appear to be exercised in the group, though in 
some, as in the American Aurelia flwvidula, the female has 
yellow ovaries, while the male shows roseate spermaria, 
Nor is the habit followed by Tealia crassicornis in coating its 
column with gravel (as some sea-urchins do with their 
bodies), or still more conspicuously with white shell-fragments, 
in harmony with the views concerning warning coloration. 
The colours of Echinoderms are often most conspicuously 
bright, as, for instance, the blues, reds, and purples of 
Asteroids, the blues, reds, and variegated red and white of 
Kchinoids, the reds and purples of Crinoids and Ophiuroids. 
It may be that it is in consequence of these bright colours 
that some authors have fancied that sea-urchins exhibit pro- 
tective measures when they cover themselves with bits of 
pebble and shells; but the same, as already explained, occurs 
in anemones, 
The brilliant orange-red of Hippasterias in deep water may 
subserve a purpose unknown to us, yet from analogy this is 
unlikely. Few forms are more conspicuous on the bottom of 
the sea or on the blades of tangles at low water than the 
common cross-fish, yet gulls, fishes (cod and catfishes), and 
an ally of its own (the sun-star) devour it. Thus, while its 
coloration is certainly not protective, it does not seem to serve 
as a warning or to be the result of Sexual Selection. The 
brilliant scarlet of Solaster papposa as it hangs on the tangle- 
blades makes it very conspicuous, but there is no evidence 
either as to protective or warning properties. ‘The same may 
