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leaves the Hudson and passing among the limestone and slate hills 
which are as islands, it ranges by Kingston, Bolton and Eddyville. 
From Rosendale it ranges across the northeast point of the Shawangunk 
mountains, (the grit rock of which disappears beneath it,) south to the 
Wallkill, and a few miles up that stream. . 
The clay and loam lands of this formation have long been held in 
high repute, but it is only within a few years that these light and sandy 
soils have begun to be appreciated. They are easy lands to till, and 
by means of plastering and clovering, they make soils of the best quality. 
IV. CATSKILL MOUNTAIN SERIES. 
The next group of rocks in the district under examination, and the 
most recent of the consolidated formations, is that which lies between 
the Helderberg limestone series, and the coal bearing rocks of Carbon- 
dale in Pennsylvania. It contains the " olive sandstones," " dark co- 
loured shales," and " black slate" of groups 8 and 9 of Mr. Conrad's 
Report of 1839 ; and formations viii. ix. x. and xi. of Professor Rodger's 
Report on the geology of Pennsylvania for 1838, viz : the part of the 
" olive slates" above the limestone formation, the " red sandstones and 
shales," the "sandstones and conglomerates," and the '^red shale of the 
anthracite coal regions." 
The Catskill mountain series consists of coarse and fine grits, gray- 
ish, greenish and various shades of red and brown, which lie thick bed- 
ded, with water lines of deposition strongly marked where a cross frac- 
ture exhibits the structure ; conglomerates of various degrees of coarse- 
ness, grayish, greenish and red ; slaty sandstones, with slates and shales 
of various colours, as red, green, spotted, gray and black. 
Testacea are the principal fossils of the lower, and plants of the up- 
per portions of the series. 
The general arrangement of parts of this series is 
1. Conglomerates and coarse grits. 
2. Red shales, slates and grits. 
3. Gray slaty grits. 
4. Chocolate grits with red shales and slates. 
5. Gray grits and bluish shales, among which are the flag stones, 
6. The olive slates and shales over the Helderberg series. 
