Perhaps they too act like the venomous matter produced in the thread-capsules of the acaleph.
And throughout considerable portions of their bodies, some of the acaleph exhibit more or less distinctly this type of structure.
The medus are often termed the acaleph—a word which signifies nettles, and they are popularly known as sea nettles.
The color of this pretty acaleph varies from a greenish hue to green, with a faint tinge of red, or to a reddish brown.
It exists occasionally in considerable numbers on the internal surface of some acaleph of the ocean and of the Mediterranean.