Page:Transactions of the Linnean Society of London, Volume 12.djvu/389

Rh after a storm: thus, from the fragility of their tubes, these animals are often found at large. When in their tubes, generally but a small part is protruded, excepting the capillary tentacula, with which they seem to be searching for food in every direction by thrusting them into cavities of shells, under stones, &c.

The branchial appendages are usually coloured with orange or red whilst the animals are alive and in health, but lose their colour as they become weak or sickly, which probably arises from languid circulation.

The mouth is in front, and the under-lip usually projects so as to make the opening upwards.

All the species inhabit the sea.

Body long, with numerous articulations furnished the whole length with peduncles, and a few with fasciculate bristles; but the seventeen anterior joints have the fasciculi most conspicuous, being always erected, and remaining so after death: the first eight joints have a broad plate on the back different in structure from the rest; they are of a rufous-brown colour, shaded with purplish-black, continuing down the back in a decreasing line. The general colour of the other parts is yellowish. Beyond the seventeen first joints the peduncles are very small, and appear to be destitute of fasciculi; and they incline gradually from the sides to the back, till towards the extremity they almost meet, forming two dorsal lines: near the mouth originate numerous capillary appendages, that are five or six

Rh