ANNIVERSARY ADDRESS OF THE PRESIDENT. XXX1X 
we know that by the binding together of the volcanic ashes of former 
geological times, chiefly by silica, rocks have been formed as solid as 
greenstone. 
The communication of Mr. Anthony on the impression of the soft 
parts of an Orthoceras in a shale, frequently termed marlite, occurring 
interstratified with limestone in the group of the palzozoic rocks of 
North America, to which the name Hudson’s River group has been 
given, affords us an additional example of the excellent preservation of 
organic remains, where a fine argillaceous sediment has accumulated 
upon them. The shale or marlite in question is described as oc- 
curring of unusual thickness where the Cincinnati Astronomical Ob- 
servatory has been erected, and in it numerous fossils were discovered 
beautifully preserved; among others Orthocerata, frequently measuring 
more than three feet in length. The smaller specimens were found 
encased in a sac, this sac of an oval form, about twice the diameter 
of the enclosed Orthoceratite, enveloping its whole length, like it flat- 
tened, and with a longitudinal impression throughout. Mr. Anthon 
supposes that the Orthoceras was furnished with a fleshy body, like 
the Sepia and its kindred cephalopods, or perhaps like the Belemnite 
with its accompanying ink-bag. It will be in the recollection of the 
Society that Colonel Portlock figured similar appearances in 1843, 
the Silurian slates of Tyrone having furnished several examples ; in- 
deed he founded his genus of Koleoceras upon them, so that be 
the impressions surrounding the Orthoceratites what they may, when 
these remains have been covered over by fine sedimentary matter, 
similar appearances are observable both in America and in Europe. 
Mr. Lyell, in his paper on the structure and probable age of the 
coal-field of Eastern Virginia, describes Calamites and Equiseta, espe- 
cially the former, as found standing erect, and as not confined to one 
geological level, but as occurring at various heights in the series, and 
at points widely different. He considers that they were not drifted, 
but grew on the area where we now find them, and infers the constant 
proximity of land, the drainage of which may have supplied a body 
of fresh water. Mr. Lyell sees no character in any of the fossils of 
this coal-field inconsistent with the hypothesis that all the beds may 
have been accumulated im a lake, estuary or delta. The fossil plants 
are inferred to have been all terrestrial, while too little is known of 
_ the genus Posidonomya to permit us to reason on its habits; and as 
to the fish, Sir Philip Egerton informed Mr. Lyell that the Tetra- 
gonolepis of the British lias is accompanied by Lepidotus, a genus 
common in the freshwater strata of the Wealden rocks of England. 
The coal itself occurs in three or more distinct beds, the chief of 
which appears to be thirty to forty feet in depth, a thickness requiring 
the accumulation of a vast amount of vegetable matter to produce it. 
The mass of sandstones, shales, and remains of vegetation of which 
this coal-field is composed, reposes in a kind of basin-formed cavity 
on granite, hornblendic and other rocks of older date, the beds dip- 
ping inwards. The view taken by Mr. Lyell, that the plants grew 
where now found, having been covered up by mud and sand during 
a gradual subsidence of the whole region, is one in harmony with that 
