going all round. The glass is set in grooves in the slate and wood, and fastened with white-lead putty. I first stocked it before the emanations of the putty &c. had sufficiently gone off; and hence the plants and animals died almost as fast as they were put in, rarely surviving the first night, although the water was renewed from the sea once and sometimes twice a day. The Mullet-fry and a few Actinias alone survived the experiment, which was continued for a week.
At the end of that time I emptied it, had it carefully cleansed and rinsed with fresh water, and allowed it to remain in the open sun and air for a week, when I judged all smell from the paint had ceased.
I now refilled it. The mode in which this was done was as follows. First I laid on the bottom a stratum of stiff blue clay, varying in thickness from two inches to half-an-inch. On this a layer of small pebbles, coarse gravel, fine gravel, and sand, was put, so as to afford varieties of bottom. Then pieces of rock were carefully put in, so selected and arranged as to make arched passages and overhanging shelters, with one mass rising pyramidally to within a few inches of the surface.
The sea-weeds, attached to fragments of stone, were now introduced; the larger and heavier on the bottom, the smaller and more delicate laid on the ledges of the rocks, or inserted into the crevices. Among the former were a large tuft of Furcellaria fastigiata, two of Chondrus crispus, two of Rhodymenia palmata, one of Dictyota dichotoma, a small plant of Fucus serratus, one of Laminaria digitata (young), two tufts of Padina pavonia, and several
