MOLLUSCA. 29 
Vallancy and Dr. Span were afterwards present, 
and saw one of the snails crawl out, the others 
being dead, most probably from their having re- 
mained some days in the water. Dr. Quin and 
Dr. Rutty also examined the living snail several 
different times, and were greatly pleased to see 
him come out of his solitary habitation after so 
many years’ confinement. Dr..Macbride and a 
party of gentlemen at his house, were also wit- 
nesses of this surprismg phenomenon. Dr. Mac- 
bride has thus mentioned the circumstance :-— 
‘After the shell had lain ten minutes in a glass 
of water that had the cold barely taken off, the 
snail began to appear, and in five minutes more 
we perceived half the body pushed out from the 
eavity of the shell. We then removed it into 
a basin, that the snail might have more scope than 
it had in the glass; and here, in a very short time, 
we saw it get above the surface of the water, and 
crawl up towards the edge of the basin. While it 
was thus moving about, with its horns erect, a fly 
chanced to be hovering near, and, perceiving the 
snail, darted down upon it. The little animal 
instantly withdrew itself into the shell, but as 
quickly came forth again, when it found the enemy 
had gone off. We allowed it to wander about the 
basin for upwards of an hour, when we returned 
it into a wide-mouthed phial, where Mr. Simon 
had lately been used to keep it. He presented me 
with this remarkable shell, and I observed, at 
twelve o’clock, as I was going to bed, that 
the snail was still in motion; but next morning I 
found it in a torpid state, sticking to the side of the 
elasa,’!.* 
* Phil. Trans. (abridged) xiii. 566. 
