154 
the tertiary geology, etc. 
I)laut8 have been described from the deposits of this group by Lesquereux, by whom 
tliev were considered to indicate a horizon more nearly Miocene than Eocene, but 
tl.ere can be but little doubt from the position of the beds containing them that they 
belong to tlie same period to which the greater part of the northern Mississippi lignite 
itself belongs— tlie lower Eocene. The Bluff Lignite, underlying the Quarternary 
gravels of the Mississippi Bluffs, consist in large part of a series of interstratified 
sands and clays, “ characterized by the presence of well-marked beds of lignite.” Its 
development appears to be at least 100 feet. 
Illinois. 
'I'he Tertiary deposits of Arkansas and Tennessee are continued through the south- 
east and southwest extremities respectively of the States of Missouri and Kentucky 
into Illinois, where they form the head of the Missi.ssippi embayment. The series, 
represented by variously colored sands and clays, and ferruginous conglomerates, has 
thus far been identified only in the southern part of the State (with a principal 
development in Pula.ski County), but not improbably, as has been suggested by 
M'orthen, marine or Huvio-marine deposits of the same ago may occur considerably 
higher up the Mississippi valley. * A green marly sand, resembling in its lithological 
characters the Cretaceous greensand of New Jersey, constitutes a marked feature of 
the formation in Pulaski County, and from it have been obtained casts of fossils 
IH-rtaining to the genera Cncullwa and Tarritella.'\ 
\ thin iM'd of lignite is stated to underlie the formation along the edge of the 
Ohio at Caledonia, constituting in that vicinity the lowest visible member of the 
s<'ries. 
XoTK Sim -0 llio .].n-i.iiratiou of the forogomg article, I am informed by Piof. Sues.s, of Vienna, that the 
lower liinoxtoiio UsU of the ihland of Jlalta, which were originally referred by Fuchs to tlie ‘-Aquitanian ” 
( < >ligo<-ene), and as tlie partial e<iuivalents of the Sotzka beds of the Vienna basin, belong in reality to the “First 
MiHllUTranean.” If this K- the case, then the OrUtoides Mantelli beds of the island represent a newer horizon 
lower >Ii(K-ene-thaii they do in our own country and the West Indies. In material recently received from 
t londa I Ibid gn-at quantities of Ortdtoidet epUpinam associated with the other forms. 
h.-U the “Virginias,” for February, 1883, and October, 1883, will bo found detailed accounts, by Prof. W. 
.1. lontane and the laU- Prof. W. B. Rogers, of the 907-foot artesian boring at Port Monroe, on the peninsula, 
alsnit 0 inih-s to the east of Newport News. 
fart.bi.Ti I.lv ! 'r map the Cretaceous exposures in the Tertiary area (North Carolina, South 
e H-en, or convenience, omitted ; likewise the exposures of the Eocene in the Miocene tracts. 
* “treologieal Survey of Illinoi.s,” i, p. 46, 1866. 
7 u JiVertT u*'refV.mTl*''a^ considered to be specifically unidentifiable, but on p. 423, the 
urrUcHa is ixfern-d, although with doubt, to T. Mortmi, a distinctively lower Eocene fossil. 
