244 
Museum during four years, when the existence of an apparently re- 
cently formed epiphragm being observed, it was removed from the 
tablet and placed in tepid water, and in a short time crawled away. 
It fed on cabbage-leaf, and began very soon the completion of a re- 
pair of the aperture of its shell, which had been broken prior to its 
capture, the suspension of animation having arrested the execution of 
the work. It resuscitated on the 15th of March last, but has shown 
neither signs nor result of fecundation, although still living. 
I am indebted to Mr. T. Vernon Wollaston (who interspersed his 
entomological pursuits, during a two seasons’ residence on the island, 
with a no less fruitful and valuable research in terrestrial eoncho- 
logy) for several species of living mollusks, principally Helices, indige- 
nous to Madeira and its adjacent rocks: all these had lain in a box in 
dry canvas bags for a year and a half, and had been restored to vitality 
by placing them in water. They were put under glass shades, on 
flower-pots filled with mould, or in large glass cases, and all fed well. 
Three individuals of the Helix undata of Lowe, within forty hours, 
deposited more than two hundred small, white, semipellucid pearl-like 
eges, which, on exposure to the air, soon became of an opake white ; 
not in a covering, nor agglutinated, but together, loose in the earth. 
One portion or nidus, about sixty in number, I immediately restored 
to their situation, about three-quarters of an inch below the surface, 
covering them with mould, hoping therefrom to learn the period of 
incubation. The parents burrowed their heads and bodies into the 
earth, remaining in that position some twenty or thirty hours, or 
forced themselves, shell and all, below the turf, and so deposited their 
ova. Other species have also produced eggs. 
Curious and instructive as these facts may be, perhaps the conti- 
nuance of the vital principle in mollusks removed from their native 
element may seem still more so, especially in the case of a bivalve, 
which has so much less perfectly the power of excluding the influence 
of atmospheric air on its animal substance; yet the latency of ani- 
mation is a quality obviously necessary for the inhabitants of ponds 
and other shallows, which of course at certain seasons are liable to be 
dried, or the existence of the species would soon become extinct. An 
Unio, which lives in ponds, and much resembles the British species, 
Unio tumidus of Retzius, but is somewhat higher and shorter, was 
packed up by the Rev. Robert King, on the 26th of January 1849, 
at Wide Bay in Australia, having been enclosed in a dry drawer for 
231 days, but was first submitted to the test of water, when its valves 
opened and it was alive. On its arrival at Southampton about the 
~ latter end of June 1850, 498 days after it had been taken from the 
pond, Mr. Newnham, to whom it was consigned, in consequence of 
what Mr. King had written, a second time placed it in water, when it 
expanded its valves and was living. It was then forwarded, inter alia, 
to the British Museum, and is restored to its element with full vital 
powers, in the care of Dr. Baird of that establishment, to whom I am 
indebted for this relation. 
I have now living, the Helix Fraseri, Australia; H. lactea, Africa ; 
H. turricula, Madeira; H. laciniosa, Madeira; H. undata, Madeira ; 
H. tectiformis, Madeira; and the Carocolla Wollastoni, Madeira. 
