No. 50.] 
455 
Rochester Shale » 
Limestone. 
2d Green Shale. 
Iron ore. 
Pentamerus Lime- 
stone. 
Iron ore. 
1st Green Shale, 
t Medina Sandstone, 
red marl and shale. 
Asaphus longicaudatus, Platynotus Boltoni, Ho- 
monolotus delphinocephalus, (Trimerus del- 
phinocephalus,) Bumastis Barriensis, Caly- 
mene Blumenbachii,* Strophomena depres- 
sa, S. elliptica, S. modesta, Delthyris — , Or- 
this — , Caryocrinus ioricatus, C. Ornatus, 
Gorgonia assimilis. 
I A large species of Orthis. 
r Calymene Blumenbachii, C. bufo, Agnostis, 
< Tentaculites, Orthis — , Strophomena — , 
V Graptolites — , 
> Fossils similar to those above and below. This 
S mass is mostly wanting in the 4th District. 
> Pentamerus oblongus, Cateniphora labyrinthi- 
S ca, Favosites, &c. 
I Fossils as above and below. 
5 Calymene, Delphinula — , Atrypa — , Stro- 
( phomena depressa, Gorgonia. 
Upper grey portions — Dictuolites Beckii. Be- 
low red and variegated — Lingula cornea, 
Planorbis trilobatus, Cyclostoma pervetusta. 
Cytherina, Fucoides Harlani, F. . 
r Of specimens illustrating the geology of the 4th District, there have 
been collected and deposited in the Geological Rooms, at the Capitol, 
thirty boxes, exclusive of those sent from Cattaraugus county by Mr. 
Horsford. 
JAMES HALL, 
State Geologist. 
* It has been remarked that this fossil is found only in the Trenton limestone, and 
ceased to exist with the deposition of that rock. During the first season of my exa= 
minations in the 4th District; I found several fragments of this fossil, and during the 
last year I have obtained some fine and perfect specimens from the Rochester Shale. 
The same species, var. major, of Murchison, occurs in the shell grit of Eaton. It oc- 
curs also in the Green Shale below the Rochester Shale. See State Cabinet. 
t This rock is the lowest in the 4th District, it being found bordering the shore of 
Lake Ontario, from Niagara river to the eastern limits of Wayne county. The Sal» 
mon river group, however, forms the bed of the lake, and in some places is probably 
at no great distance from the shore, as boulders and pebbles, containing the peculiar 
fossils of that group, are found on the lake beach in Niagara county and other places, 
and I have seen the same rocks in place on the north side of the lake, a few miles west 
of Toronto, 
