429 PROCEEDINGS OF THE NATIONAL MUSEUM. vou. xxxvv. 
and 5 of shale were noted in the section. It is possible that the orig- 
inal distribution of the formation was equivalent to that of the under- 
lving Beech River, and that erosion preceding the advance of the 
sea 1n which the succeeding formation—the most widespread of all— 
was laid down, has removed these strata, particularly in the more 
northern areas. 
Although we might have adopted the term “ Gant formation ” for 
these limestones and shales with an abundant and characteristic brach- 
iopod fauna, we came to the conclusion that the name had better not 
be employed. At present there is scarcely any exposure at the original 
Gant locality, and in a few years vegetation will have completely 
covered the rocks here. The place is found with great difficulty, 
and, moreover, Gant no longer lives there. The term is not a geo- 
graphical one, and, in addition, the entire section is not developed 
there. An excellent exposure of these strata occurs about 1 mile 
from Swift on the Swallow Bluff road where the shales and lime- 
stones hold fine specimens of the brachiopods. Here the limestone 
layers, usually present at the base of the formation, have disinte- 
grated in shaly material and the large Uncinulus stricklandi noted in 
this particular bed occur free. 
Typical “ Gant” limestone and clays are also well exposed on the 
west side of Buffalo River in Perry County, at Beardstown. The 
section along the Tennessee River in the vicinity of Bob is by far 
the most complete and conspicuous, and it seemed most fitting, as 
stated above, to apply this new name to the formation. 
The uppermost division of the Bob formation is of nodular, cherty 
limestone or hard shale in which brachiopods of the genus Con- 
chidium are the most characteristic fossils. On the east side of the 
Tennessee River this zone, to which we have applied the name Con- 
chidium, is well shown in the Lady’s Bluff section, while west of the 
river good exposures are found at Brownsport Furnace. 
LOBELVILLE FORMATION. 
The third formation here recognized is characterized paleontolog- 
ically by a fauna of corals so abundant in species and specimens that 
the identification of the beds is attended with little difficulty. These 
corals are most abundant in the upper half of the formation, and 
wherever their strata are well exposed many fine specimens may be 
had. Halysites catenulatus, so abundant at Louisville, Kentucky, in 
the late Niagaran, is represented in the West Tennessee strata, 
with the exception of the Clinton, only at this horizon. The same 
occurrence in the late Niagaran only, holds true for almost all of 
the following species, likewise very characteristic of the Louisville 
coral bed: Alveolites lowsvillensis, A. niagarensis, Amplexus shu- 
mardi, Cladopora complanata, C. reticulata, Coenites verticillata, 
