300 
GEOLOGY OF THE FIRST DISTRICT. 
various degrees of coarseness, greyish, greenish and red ; slaty fissile sandstones, with slates 
and shales of various colors, as red, green, and mottled with these colors, grey and black. 
Testaceous fossils are extremely rare. Terrene and marine plants are more common. 
The following engravings, figures 7, 9, 10, 11, 12, 13, illustrate some of the fossils of this 
division of rocks: 
Fig. 6. 
Fig. 7 
