Page:The aquarium - an unveiling of the wonders of the deep sea.djvu/280

Rh the mantle are visible in aculeatum also, but in tuberculatum, they are much more strongly marked, both in form and colour. The siphons display the same orange hue as the mantle-lips, and have a finer appearance than in the other species; the interior of the orifices, in both, is covered with a layer of white pearly substance, almost luminous. In the foot of tuberculatum, which agrees in the particulars already mentioned with that of its congener, I observed a beautiful opalescent gleam, when under water.

I had supposed that they would display their instincts to more advantage if placed in circumstances more accordant to their habits. I therefore first imitated the sandy beach from which the tide has just retired, by laying my protegès on a bowl of wet sand; and afterwards placed them in a large vessel of sea water with a sandy bottom of several inches deep. But in neither case was there any correspondent action in the animals; they did not attempt to burrow, nor were they so active as when in the clean dish. Most of them soon died; one only, a large specimen of C. aculeatum, lived about ten days, in the circumstances last mentioned, content to lie submerged on the top of the sand; though the siphons, mantle, and foot indicated health, until the last day or two of its life. Sickness is marked, in these animals, by the lax state of the mantle, which permanently recedes from the foot, and gapes; by the softness of the foot, which is partially protruded; and by the shrinking of the siphons.

A considerable number of those sent up we "killed to save their lives;" making gastronomical use of