Proceedings. 23 
Committee. Rev. R. Ashington Bullen, Dr. T. A. Chapman, 
Mr. J. B. Crosfield, Rev. G. Currie Martin, 
Mr. D. P. Poulter, Mrs. Powell, Messrs. C. E. 
Salmon, A. Trower, and W. H. Tyndall. 
The Rey. R. Ashington Bullen, F.L.S, F.G.S., exhibited a 
specimen of Carborundum, a compound of carbon and sand, 
which is hard enough to cut glass. It is very brittle. 
He also exhibited the following :— 
Opisthostoma (from Colonel Beddome’s collection).—The 
peculiarity of this genus of land molluscs from Borneo is that 
the last or body-whorl is reflexed backward, so that the entrance 
to the shell is in an exactly opposite direction to the general 
trend of the whorling. The following species of Opisthostoma 
were shown :—0. lintere (Sow.), 0. de Crespignyi (H. Adams), 
O. Everettii (E. A. Smith), O. Baritensis (E. A. Smith), 
O. Wallacet (Ancay), O. mirabile (E. A. Smith), O. pulchella 
(Godwin-Austen), O. jucundum (E. A. Smith), O. Busanense 
(E. A. Smith), O. otostoma (Boettiger). 
Molubdides or sling-bolts from Marathon (Forman Collection), 
probably relics of the battle between the Greeks and Persians, 
B.C. 490. 
The sling-bolts exhibited were of lead, of an elongated 
elliptical form. 
Helicigona arbustorum.—The specimens of this land-shell were 
from Derbyshire, at high altitudes, viz.: Buxton, Lovers’ Leap, 
950 feet O.D.; above Poole’s Cavern, Buxton, 1200 feet O.D.; 
and up the Winnats Pass, Castleton, 1250 feet O.D. Locally, 
it used to occur at Redhill in the osier-bed near the Railway, 
which seems to have disappeared: it also is found in the 
Holocene deposit at the Horseshoe at the lower levels. 
This species occurs in Pliocene, Pleistocene, and Holocene 
deposits. 
Vitrea alliaria.—This mollusc exhales a strong sent of garlic, 
hence its name. This peculiarity is not confined to this species. 
One specimen was found in the Holocene deposit at the Horse- 
shoe Pit, Colley Hill. 
