34 
THE GEOLOGIST* 
found are Terebratulse, several pieces of Catenapora, Calamipora, 
Columnaria tubipora, Aulopora, Sarcissula, Astrea, Cyatho- 
pliylla, Caryophylla and Othocerites. 
Middle Beds, — Aspect more arenaceous^ though it contains 
but a small per centage of sand. Chert masses are rare. 
Stratification imperfect, and numerous vertical fissures. Rich 
in ores of lead and zinc, associated with iron in small quantities. 
The fossils are Coscinipora (sulcata ? Gr.) — ^the only coralline, a 
Oirrus resembling perspectivus ; Ampullaria, also impressions of 
spiral univalve, resembling Vivipara. It seems by the above 
that there is no absolute geological distinction between the mid- 
dle and lower beds. 
Lower Beds. — Also of arenaceous appearance, rather more 
distinctly stratified than the middle beds, and imbedding more 
frequently th^n these siliceous chert masses. They contain the 
same fossils and ores as the middle beds, with the addition of 
copper and sulphate of zinc. 
April 26th, 1842.— Dr. Morton in the chair. Prof. Hitch- 
cock submitted a paper " On the Phenomena of Drift in the 
United States.'' This essay was accompanied by a chart exhi- 
biting the course of strise and lines of dispersion of boulders. 
Dr. Jackson objected to the remarks of Prof. Hitchcock on 
the ground that if we admit several different causes, it would be 
improbable that we should find that they had acted in nearly the 
same direction. The United States exhibit no proofs of the 
glacial theory as taught by Agassiz, but on the contrary the ge- 
neral bearing of the facts is against that theory ; for we observe 
nowhere in that country a general radiation of detritus from 
the principal mountain ranges, although as in Ehode island, 
there is a divergence from the point whence the boulders are de- 
rived. This divergence is, however, merely a spreading of fifteen 
miles for forty in extent, and it is in the usual general direction 
of North American drift, to the southward ; none of the boulders 
having been drifted to the north of their parent bed. Mr. Lyell 
offered some remarks with reference to observations in Europe 
