APPENDIX. 239 
PLATE: V. 
CORALS AND SEA ANEMONES. 
CaRYOPHYLLAA Suita. Pl. V. fig. 2. Pl. VI. fig. 3. 
THE connection between Brainstones, Mushroom 
Corals, and other Madrepores abounding on Poly- 
nesian reefs, and the “Sea Anemones,” which have 
lately become so familiar to us all, can be seen by 
comparing our comparatively insignificant C. Smithi 
with our commonest species of Actinia and Sagartia. 
The former is a beautiful object when the fleshy part 
and tentacles are wholly or partially expanded. Like 
Actinia, it has a membranous covering, a simple sac- 
like stomach, a central mouth, a disk surrounded by 
contractile and adhesive tentacles. Unlike Actinia, 
it is fixed to submarine bodies, to which it is glued 
in very early life, and cannot change its place. Un- 
like Actinia, its body is supported by a stony skeleton 
of calcareous plates arranged edgewise so as to ra- 
diate from the centre. But as we find some Molluscs 
