284 
[Assembly 
tie sandstone, and with the same characters in Oneida to near Rome, 
where another, but a small series of shales and sandstone are met with, 
which north and west in Oneida, are co-extensive with the lower mass. 
Fossils are rare in the lower one^ the most common is the Crytolithus 
tessellatus, and the pentremites. In the upper mass, they are remarka- 
bly abundant as species and individuals, the most characteristic are the 
Pterinea's carinata, P. modiolaris, P. pholadis, Gyrtolites ornatus, Pro- 
ductus planulata and Pleurotomaria terebralis and Bellerophon striatulus. 
With these fossils there is the recurrence of the Delthyrus striatula of the 
Trenton limestone. 
" Millstone Grity — All the preceding rocks are below this mass, all 
passing under it. This rock is the first mass of pebbles met with in the 
series. The pebbles are of glassy quartz, same with those met with in 
the calciferous, only more water worn. Nothing extraneous in this 
rock, but pyrites and a few large imperfect fucoides. 
North of Wood creek and Oneida lake, the green and red sandstone 
follow the last described series, but south of the Mohawk, the grit fol- 
lows that series, and upon the grit reposes the protean group. The gray 
and red sandstone, within the limits examined, presenting no well de- 
fined common character of union with the protean group, requires more 
extended observation west, to remove the ambiguity occasioned by the 
absence of the grit in Oswego. 
Protean Group. — This mass is about two hundred feet in thickness, 
consists of green and blue shales, green, red and white sandstones, red 
oxide of iron, gypsum, &c. The red sandstone of Herkimer, shows 
that the iron has passed through the mass by infiltration; much of it 
presenting its grains of sand enveloped by minute crystals of oligiste or 
specular iron, the appearance which belongs to the red oxide, when in a 
crystalline state. 
This group abounds in fucoidesj many of the species are new; in 
none of them could the Harlani of Oswego at Fulton, of Medina, Ro- 
chester and Lockport be discovered. The characteristic Crustacea is a 
trimerus, probably the delphinocephalus. Shells exist, but not common, 
themost abundant is a Leptcena, like the planulatus. 
Red Shale. — Mass uniform as to composition and colour, with the ex- 
ception of a few thin layers of green shale, and gray sandstone, and 
gpots of gTeen shale. No fossils, 
