EXPLANATION OF PLATES. 
PLATE XXV. 
From the Hudson slate to the Catskill group. 
Fig. 1 and 2. Faults in the Barnegate limestone, Barnegate, Dutchess county. 
3. Section at Sharon springs, Schoharie county. 
4. Section at High falls, Ulster county. 
5. Section of the Helderberg series, Schoharie county. 
6. Section from Esperance in Schoharie county, to Deep clove in Ulster county. 
7. Section at Deep clove. 
8. Section at Stone clove, Greene county. 
9. Fossil plant stem in the Catskill mountain rocks, Durham, Greene county. 
PLATE XXVI. 
Hudson slates, Shawangunk grit, and Helderberg limestones. 
Fig. 1. Section on the right bank of the Rondout, Ulster county. 
2. Topographical sketch of the anticlinal axis at Two-ponds, Ulster county. 
3. Section across the above axis at Two-ponds. 
4. Section across the same axis, half a mile above Lawrenceville. 
5. Across the same axis, at Lawrenceville. 
6. Across the same, on the Shawangunk mountain. 
7. Near the same axis, between Rochester and the Shawangunk mountain. 
PLATE XXVII. 
Quaternary. 
Fig. 1. Section of a gravel bank near Hudson. 
2. Topographical sketch of beach and marsh near Southold, L. I. 
3. Section of the above. 
4. Section on the west side of Newburgh bay. Orange county. 
5. Section from Lower Redhook landing, east two miles, Dutchess county. 
6. Section at Grassy point, Rockland county. 
7. Section between the Hudson river and Norman’s kill, Albany county. 
8 and 9. Limestone and quaternary at Hurley, Ulster county. 
