EXPLANATION OF PLATES. 
PLATE XXVIIL 
Primary to Quaternary. 
Fig. 1. Section from Lake George in New-York, to Poultney in Vermont. 
2. Section at Mr. Goulard’s farm in Putnam, Washington county. 
3. Section across the Twelve-mile marsh on Lake Champlain. 
4. Topographical sketch of the Hudson from Barnegate to Fishkill, Dutchess county. 
PLATE XXIX. 
Fig. 1. Topographical sketch of the Hudson from Oakhill ferry in Columbia county, to 
Lower Redhook landing in Dutchess county. 
2, A like sketch from Garrison’s point to Hydepark. 
3. Section of the Catskill mountain rocks in Sullivan county. 
PLATE XXX. 
Primary and Metamorphic. 
Fig. 1 and 2. Contorted wrinkled limestone at Peekskill bay, Westchester county- 
3. Plane and wrinkled limestone at the same place. 
4. Topographical sketch of Sterling mines and vicinity. 
5. Section across the above. 
6. Sketch of a granite vein traversed by quartz veins. 
7. Sketch of the extent of limestone on New-York island. 
PLATE XXXI. 
Quaternary. 
Fig. 1, 2, 3. Sections of the gravel pits on the Patroon’s creek, Albany county. 
4. Section of the clay and sand beds on Arbor hill, Albany county. 
5 and 8. Faults of the clay and sand beds at the same place. 
6 and 7. Wrinkled clay beds wedged between plane ones ; same place. 
9. Section of striped blue clays : same place. 
PLATE XXXH. 
Alluvial. 
Section of Ball’s cave, Schoharie county. 
