moves them irregularly about, they shine with a radiance resembling that of rubies and sapphires.
These elegant branchiæ seem very easily dislodged; the specimens I have kept have usually lost one or more tufts, which, however, soon begin to sprout again. They are liable to be lost through the pugnacity of the animals themselves, as their predaceous habits frequently impel them to tear off each other's papillæ.
In captivity, this Eolis is very active, continually gliding with a uniform motion around the sides of the vessel, or climbing about the numerous branching sea-weeds that are growing in it. They frequently crawl close to the edge of the water, but never come actually out, though they occasionally float at the surface, by means of the expanded foot, back downwards.
Another species (E. punctata) has been heard to make that peculiar clicking sound, already mentioned as produced by Tritonia.