404 
GEOLOGY OF THE SECOND DISTRICT. 
No. 3. The S. nasuta, is abundant in the lower part of the grey sandstone, to be described 
in the next section. 
No. 4. The Cypricardites modiolaris, is one of the fossils which, along with the Pterinea 
carinata, appear strictly confined to this rock. Neither of them have left any vestiges in the 
trenton or utica slate. 
113. 
No. 1. Orthoceratites asqualis. 3. Pleurotomaria. 5. Orthis crispata. 
2. Avicula demissa. 4. Orthis testudinaria ? 6. Tentaculites. 
No. 1. The Orthoceratites cequalis is quite abundant in the shaly or more sandy part of 
this rock. A much larger one resembles this, and appears common in the same stratum ; and 
another also resembling it, is found one hundred feet below, but it is quite rare. 
No. 2. Avicula demissa is found in the lower part of the grey sandstone : this is also rare. 
No. 3. Pleurotomaria -, occurs in the soft argillaceous mass near the top of the rock. 
No. 4. Orthis testudinaria ? It is impossible to decide with certainty whether this is the 
true testudinaria, or the one so called in the trenton limestone. Each figure is a drawing of 
the difterent casts, which will be recognized by inspection. 
No. 5. Orthis crispata, is associated with the preceding, but is not so abundant at Loraine. 
The Tentaculites -, is very common in this rock; at Loraine, it is more abundant near 
the upper part of the rock. 
