Nullipores Sponges of the Boulder Clay of Caithness. 101 
tions have been destroyed ; there is, however, no douht about 
the genus. Many species " existed during several geological 
periods ; for instance, in the Crag, in the London Clay, in the 
Paris Basin, in the Chalk, in the Greensand, and in the Oolite. 
Mr Alder has detected it in a specimen of Pecten islandicus 
from a raised beach at Bute," and to this list is now to be 
added the boulder clay of Caithness. Many species of Clionia 
also now exist in our seas, as shown in Mr Hancock's delight- 
ful paper, published in the 3d vol., second series, 1849, of the 
" Annals and Magazine of Natural History," from which the 
above quotations were taken. I again beg to apologise for so 
long delaying this paper. I trust that the additional matter 
and facts collected by that delay will plead an excuse for me. 
It is pleasant, when working in this once said to be barren 
field, to be rewarded by adding to the shells of the age, first 
zoophytes, and now sponges and plants. 
Wednesday, 27th April 1859. — T. Strethill Wright, M.D., 
President, in the Chair. 
Thomas Boyle Grierson, Esq., surgeon, Thornhill, Dumfriesshire, 
was elected a non-resident member. 
The usual Committees were appointed for conducting special investi- 
gations during the recess. 
The following donations to the Library were laid on the table : — 
Memoirs of the Literary and Philosophical Society of Manchester, new 
series, vols. iii. to xiv., and part 1 of vol. xv. — From the Literary and 
Philosophical Society of Manchester. M ^moires de la Societe Iraperiale 
des Sciences Naturelles de Cherbourg, tome v., 1857. — From the Society. 
The Canadian Journal of Industry, Science, and Art, new series, No. 
xix., January 1859. — From the Canadian Institute, Toronto. Premiere 
Centurie de Longicornes du Vieux Calabar. Par Auguste Chevrolat. 
Paris, 1858. — From the Author. 
The communications read were as follow : — 
I. Report on the Pearl BanJcs of Arippo, Ceylon, for Season 1858, By 
E. F Kelaart, M.D. Communicated by Dr R. K. Greville. 
In this paper the author states that he found in most of the 
pearl-bearing shells a worm (a species of fllaria), which he 
