Geological Socicty. 73 
series of vertebral animals, the species of which become more and 
more numerous, and more and more diversified, as well in their forms 
as in the details of their organization. 
The old red sandstone, including the Caithness schist and the Gam- 
rie deposit, contains twenty species. 
In the coul measures there are fifty-four species ; in the magnesian 
limestone sixteen. 
The oolitic series is particularly rich in ichthyolites, the number of 
species from the lias to the Wealden inclusive being one hundred 
and fifty. 
The greensand and chalk are also very rich in fossil fishes, and 
even much richer than their equivalents on the Continent. The num- 
ber of English species is fifty. 
In the London clay the species perfectly determined are about fifty, 
but it is certain, from the fragments preserved in different collections, 
that this formation incloses the remains of a much greater number. 
M. Agassiz stated that the London clay, particularly in Sheppey, will 
be, for a long time, an inexhaustible mine. 
The crag contains five or six species peculiar to it, and belonging 
to genera which do not inhabit our northern seas. 
As an example of what remains to be done in the study of fossil 
fishes, and of the importance of these researches to zoology and geo- 
logy, M. Agassiz afterwards described two singular genera found in 
the lias. One is the animal which has been described under the name 
of Squalo-raia, discovered at Lyme Regis ; the other a new genus, 
called by M. Agassiz Gyrostris mirabilis, and is probably the largest 
known fish. This fossil was discovered at Whitby; but there have 
hitherto been found only some detached bones of the head, of the 
branchial arcs, and some portions of vertebra and fins: traces of the 
same fish have been recently observed at Lyme Regis. 
Nov. 18.—A letter was first read from Dr. Pingel of Copenhagen 
to the President, containing a notice of some facts showing the gradual 
sinking of part of the west coast of Greenland. 
The first observations which led to the supposition that the west 
coast of Greenland nad subsided, were made by Arctander between 
1777 and 1779. He noticed, in the firth called Igalliko (lat. 60° 43’ 
N.), that a small, low, rocky island, about a gun-shot from the shore, 
was almost entirely submerged at spring tides, yet there were on it 
the walls of a house 52 feet in length, 30 feet in breadth, 5 feet thick, 
and 6 feet high. Half a century later, when Dr. Pingel visited the 
island, the whole of it was so far submerged that the ruins alone 
rose above the water. 
The colony of Julianahaab was founded at the mouth of the same 
firth in 1776; and near a rock, called the Castle by the Danish co- 
lonists, are the foundations of their storehouse, which are now dry 
only at very low water. 
The neighbourhood of the colony of Frederickehaab (lat. 62° N.), 
was once inhabited by Greenlanders ; but the only vestige of their 
dwelling is a heap of stones, over which the firth flows at high water. 
Near the well-known glacier which separates the district of Fre- 
Third Series. Vol. 8. No. 43. Jan. 1836. L 
