294 Lower- Helderberg Rocks of Port Jervis, etc. 



2. Coral or " Favosite " Limestone, from four to six 

 feet thick. This particular stratum is full of large corals, 

 principally favosites, among which F. JSfiagarensis ( ?) pre- 

 dominates. It is also filled with the fragments of uncle- 

 termined crinoids, and contains besides, Chwteies, Stromal- 

 oporoe, and Pentamerus galeatus. 



3. Lower Pentamerus Limestone, fifty feet thick, and 

 divisible from below into, — 3«, a coarse-grained limestone, 

 twenty-five feet, with bands of Pentamerus galeatus; and, 

 36, shaly with layers of chert, twenty-five feet, less fossil- 

 iferous than the preceding. 



4. Delthyris Shale, a hundred and seventy-five feet. 



5. Upper Pentamerus Limestone, two hundred and fifty 

 feet. It exhibits three divisions, viz. — ha; a coarse-grained, 

 cherty, grayish limestone, ten feet thick, probably the equiv- 

 alent of the Encrinal Limestone, though I have not seen the 

 crinoids; 5b, shale, rather sparingly fossiliferous, 235 feet; 

 5c, trilobite layers, five feet. All the fossils enumerated 

 further on as Upper Pentamerus, and associated with Dalma- 

 nites denlata, belong to 5c. 



6. Oriskany Sandstone, one hundred feet : it is probably 

 more, the higher arenaceous layers of this division having 

 been removed by glacial action. 



7. Cauda Galli Grit, from five to eight hundred feet in 

 thickness. 



These sub-divisions are all encountered in a succession of 

 terraces rising one above the other. Between the Oriskany 

 and Cauda Galli there is generally a hollow with turbary de- 

 posits. 



FOSSILS IDENTIFIED. 



Those marked with a * were identified by Professor Hall. 



From (1) : — Leper ditia alia, *Beyrichia notaia, Tentacu- 

 lites gyracanthus, Loxonema Fitcldana, L. obtusa, Holopea 

 untiqua, H. elongata, * Megambonia ovoidea, *Spirifer Va~ 

 nuxemi, and * Strophodonta varistriata. The gasteropods 

 and other fossils seem to aggregate in layers or thin bands. 



