Geological Society. 297 
ing centres present no trace of a wall, others possess walls 
more or less incomplete; but the centres are easily distin- 
guished by the position of the pali. The septa of two or 
three cycles, generally twelve, sometimes fewer, rudimentary, 
sometimes rather distinct at their inner ends and united two 
by two where the pali are placed. The pali are six, promi- 
nent, sometimes one very small or absent. Columella incon- 
spicuous. 
Locality. 'Vahiti. 
PROCEEDINGS OF LEARNED SOCIETIES. 
GEOLOGICAL SOCIETY. 
February 20, 1884.—Prof. T. G. Bonney, D.Sc., F.R.S., 
President, in the Chair. 
The following communications were read :— 
1. **On a recent Exposure of the Shelly Patches in the Boulder- 
clay at Bridlington.” By G. W. Lamplugh, Esy. Communicated 
by Dr. J. Gwyn Jeffreys, F.R.S., F.G.S. 
During some long-continued windy weather in the early part of 
the winter of 1882-83, the Boulder-clay, usually hidden by sand 
and shingle, was laid bare on the foreshore at Bridlington Quay. 
The beds thus exposed belong to the lowest recognized part of the 
glacial series of Yorkshire, the ‘‘ Basement Boulder-clay.” Over 
this, parted occasionally by a little sand or gravel, comes the Purple 
Boulder-clay, the Laminated Clay being wholly absent. The Base- 
ment Clay thus exposed contained angular and subangular boulders, 
with rounded pebbles occasionally scratched, besides many crushed 
masses of sand, sandy gravel, and clay, forming nearly a third of the 
whole mass. The last, which generally contained marine remains, 
were very variable in shape and in lithological character. Tho 
fauna of the masses varied greatly, both in abundance and in species, 
those common in one mass being rare or absent in another. The 
shells were commonly much crushed, though whole specimens oc- 
curred occasionally. The author considered that these shell-bearing 
patches had once formed a part of the bed of a glacial sea, which 
had been invaded and ploughed up by ice, which had transported 
them to their present locality. He gave reasons for thinking that 
they have not come from the immediate neighbourhood, but pro- 
bably from the north-east, having been floated by icebergs to their 
present places. 
Ann. & Mag. N. Hist. Ser. 5. Vol. xiii. 20 
