282 Rev. R. T. Lowe on Melampus, §c. 
afra were kept for some months in a glass of sea-water. They constantly 
affixed themselves to the side of the glass above the water; at first 
indeed to the cover; but as the weather grew hotter, they descended 
lower, fixing themselves in a group to the side, a little above the surface. 
If any fell into the water, they speedily made their way out of it. When 
immersed, a bubble of air was always seen between the edge of the mantle 
and the body of the animal on the right side. No particular attention was 
paid to them, and the water often was not changed for a fortnight or more. 
They all remained quite healthy, though altogether inactive. Yet if the 
cover was left off accidentally at night, most of them were found in the 
morning to have crawled out of the glass to some distance on the table. 
No food was given to them the whole time. 
Experiment 2. 
A repetition of the preceding, for some months, with a fresh set. 
Habits precisely the same. 
Experiment 3. 
Two specimens of Melampus equalis were placed in fresh-water : the 
animals immediately shrunk within the shell, and never came out again 
while they remained in the water. One of them having been immersed 
in it an hour or two, recovered on being again placed in sea-water. The 
other which was left in the fresh-water never crawled again, and was dead 
the next day. 
Experiment 4. 
Numerous specimens of Melampus @qualis, which have lain neglected 
in a tin box among wet sponges since February 6th, I took out to-day, 
(March 10th) alive, and they crawled actively about. All the specimens 
mixed with them of Pedipes afra, (which were also numerous,) and of 
Melampus exiquus are quite dead: but others of Littorina vulgaris, 
(Turbo littoreus, Linn.,) are quite lively. 
: Iixperiment 5. 
Melampus exiguus placed in a glass of sea-water remains generally at 
the bottom: and though sometimes crawling up the sides, never remains 
aboye the surface. Nor when below, has it ever the air-bubble on the 
right side, as in Melampus equalis. 
Experiment 6. 
Another set of Melampus exiguus. They are often seen with an air- 
