90 Proceedings of the Royal Physical Society. 
air and the centrifugal force causes the net to expand like a 
flat old-fashioned umbrella, in which shape it reaches the 
surface of the water. The weight of the bullets causes the 
descent of the circumference, and the net assumes an oval 
form, and the tiny fish are caught bj the meshes in their 
attempt to escape. 
Mr Brjson also took the opportunity of reading the following 
note he had received from his friend Dr James M'Bain, E-.N. : — 
"As an additional instance of the tenacity of life in cer- 
tain species of the mollusca, I may mention that in the 
spring of 1857 a small Helix was picked out from amongst 
some dried raisins, and handed over to me by one of my fa- 
mily. As it had the thin, transparent, glistening film cover- 
ing the aperture, it occurred to me to repeat the experiment 
related by Dr Baird, in reference to the Egyptian desert snail 
in the British Museum, and included in the examples of 
tenacity of life in these animals given by Mr Woodward in 
his ' Manual of the Mollusca.' The following day our shy 
friend made his appearance in the glass vessel, and lived with 
us for five months. It was occasionally supplied with a little 
water, and portions of green vegetables, such as cabbage and 
lettuce, and seemed to give a preference to the latter. It was 
precisely identical with specimens of Heliw virgata got at 
Shotover Hill, near Oxford, along with our friend Dr Mel- 
ville in 1847. This species is widely spread over the south of 
Europe, and, although having no objection to the interior, 
yet, like ourselves, has also a strong attachment for the neigh- 
bourhood of the sea. It is not surprising, therefore, to find it 
in company with Malaga raisins ; but those singular excep- 
tions to the general laws, in the marked examples of torpidity 
in various animals, living for indefinite periods without food, 
and almost without air, are surprising." 
