Geology and Mineralogy. 473 
on the Erie railroad, a mile west. from Otisville, in New York,’’ 
the dip of the former being 28°, and of the latter 43°, the direc- 
tion in each case north-northwest; and, besides, the latter rock 
has an eroded surface and chips of it occur in the conglomerate, 
Similar saagigags of unconformability were observed at the Lehigh 
ae er ( 
prefatory letter, introductory to the Report, by 
Pier Lake: Director of the Geological Survey, we cite the 
ollowing : 
“The ‘body of the Catskill plateau consists of the Catskill adie 
tion (uppermost Devonian, No. LX of the former survey), ab 
5000 feet thick, and the peaks are what remains of the overlie 
gray Subearboniferous, the Pocono formation (No. ch 
formerly spread continuously. over ae ats <ill_ beds. 
Counties. A the latter tha Monk Aas Red shale forma- 
tion (No. XI), the Pottsy a ig lp (No. XII), and t 
Coal moeentcs (No. CIT), e lays w nce Mr. wesley con- 
North or "Al le ene Mountain nile He observes that it 
must be regarded as one broad synelinal rising cor m* the north- 
east, through which run ay eee .E. and S8.W.) gentle 
anticlinal undulations, that west of the Delaware become stee ep 
anticline 
The fac of the increase in thickness and coarseness of the 
Palectoie | pA wien beds from New York to Alabama points to, 
if it does not } prove, says Professor Lesley, “the derivation of the 
sediments from the Archean highlands of New England, South- 
ern New York, Northern New Jersey, the South Mountains of 
Pennsylvania, the Blue Ridge range of Virginia and the Black 
some of these 
which were early covered with P. 
Alps still farther off, now buried beneath the shore deposits or 
beneath the waters of the Atlantic 
Professor Lesley mentions the course of the “ terminal moraine” 
as ascertained by Mr. Lewis, who has this subject in bg but 
adds that the existence of ice-striw on the crest of oun- 
tain, west of Ashland and 25 miles south-southwest of the near est 
part o of the great moraine, suffices to show that much is yet 
uncomprehended. 
The Report contains a large colored geological map, by Mr. 
White, and sections and maps by Mr. Chance. 
3. Geolog, y of Philadelphia County and of the other parts ma 
Montgomery and Bucks Counties, by Cuarves E. Hatt, wit 
