440 Scientific Intelligence. ig 
é 
iferous, though we have not yet been able to determine definitely whether 4 
»’ 
~~ 
they are Lower or Upper Carboniferous forms; as they are for the most | 
part badly preserved, and present apparently a mingling of Coal measure 
and Lower Carboniferous types. 
4th. Two beds of a fine (rather incoherent) brick-red material, separa- 
ted by from ten to fifty feet of-bluish gray and reddish gritty limestone, 
containing specimens of a very small plicated Rhynchonella, a small 
Pleurotomaria, two species of Macrocheilus, and one or two species of 
Bellerophon, all apparently closely allied to Coal Measure forms. 
Th rick-re s above mentioned is from two 
same species, discovered by Major F. Hawn in northeastern Kansas, 1 
eds now known to be of Permian age. These masses were not seen 2 
place, and their position in relation to the other beds is consequently 
from one hundred to one hundred and fifty feet of strata, consisting of : 
series of bluish ash-colored and variegated argillaceous shaly beds, an 
dark-brown, reddish, gray, and yellowish sandstones, &c., eR 
Lingula, Avicula, Arca, Belemnites, Ammonites, Pentacrinus, &¢., all 
Jurassic types. From these facts, and the absence of Cretaceous rarer 
in this series, together with its stratigraphical position, we regard 1 
belonging to the Jurassic system. 4 feet 
6th. Then comes a series of strata, together about four hundre 
in thickness, very similar to the beds just mentioned, and not separt 
from them by any well-marked line of demarkation. In the lower te 
of this group, an Ammonite, a Planorbis, a Paludina, and a Unio we of 
found, but most of the entire series of beds appear to be bape 
organic remains excepting fragments of vegetable matter. 7 : ibe 
we regard as probably belonging to the older Cretaceous, (No. i 
published sections ‘of Nebraska Cretaceous formations,) though a Jarge 
portion of them may be Jurassic. - a Nay 
Above all the foregoing formations we have in regular succession | gee 
2, No. 3, No. 4, and No. 5 of the Cretaceous series of Nebraska, 4 gs! 
in the published sections. t Creta- 
; ane rocks, from the Potsdam sandstone to the , psc and all, 
ceous, inclusive, a to repose conformably upon each others © 
