22 GEOGRAPHY AND GEOLOGY OF RAMPART REGION. 
Fossils from near Yukon Flats and from Hess Creek, Alaska. 
4 AH 213. 
Stenopora, two sp. Rhombopora sp. 
Fenestella sp. Productus ? sp. 
Rhombopora sp. Lima ? sp. 
4 AP 270. 
Fistulipora sp. Rhombopora sp. 
Strom^topora ? sp. Rhombopora sp. 
Coral sp. Spirifer n. sp. ? 
Fistulipora sp. Hustedia of. H. compressa Meek. 
Fistulipora? sp. 
4 AP 277 
Coral ? sp. Polypora ? sp. 
Lithostrotion ? sp. Archimedes ? sp. 
Fistulipora 3 sp. Productus sp. 
Rhombopora sp. Euomphalus sp. 
The presence of the form identified as Hustedia compressa seems to show that lot 270 belongs in the 
Pennsylvanian, perhaps in the Permo-Carboniferous. The ages of the other lots, although without 
much doubt being Carboniferous, are less certain. While probably no species is common to all three 
collections, yet in a general way the facies is much the same, and it is quite possible that all repre- 
sent the same fauna. 
It will be observed that only in one case have the forms collected been identified specifically. In 
many instances the material is too imperfectly preserved to admit of more than the genus being 
determined. In others the species are distinct from those of the Mississippi Valley sections, and 
entirely new unless some of them have been described in European and Asiatic publications not 
included in my bibliography and therefore difficult of reference. 
I have consulted freely with Mr. Bassler wherever the Bryozoa were concerned. 
CRETACEOUS. 
High up on the flanks of the Wolverine and Lynx mountains are black, rather mas- 
sive, impure sandstones and shales. In the sandstones of Wolverine Mountain, 
which form great rock piles along the upper parts of the spurs at an altitude of over 
1,000 feet above the base of the mountain, were found fragments of dicotyledonous 
leaves and a part of an indeterminable bivalve. The shales, also, were found to 
contain a few obscure plant remains. The only positive result obtained is the fact 
that there are rocks occupying the highest parts in the area, which are at least as young 
as the Lower Cretaceous and far younger than the rocks of the lower slopes of Wol- 
verine Mountain, where limestones w T ere found containing corals, the stratigraphic 
value of w r hich is sufficient only to determine the, age as either Silurian or Devonian. 
They rest on the upturned edges of the older rocks and have themselves undergone 
considerable deformation. Just how much is to be included with these rocks has 
not been determined. The associated black, carbonaceous, slaty shales are like 
those closely associated with the rocks regarded as Devonian. The black, sandy beds, 
in which the fossils were found are unlike those observed elsewhere and resemble the 
Upper Cretaceous rocks which occur lower down the Yukon. They are entirely 
different from the Kenai rocks near Rampart and are referred provisionally to the 
Cretaceous. 
Rocks determined as Kenai occur along the Yukon above Rampart and are found 
also for a short distance up the valley of Minook Creek, where they contain a small 
amount of coal. There are conglomerates, sandstones, and clays resting unconform- 
ably on the older rocks. The degree of consolidation is hardly sufficient in some 
cases to withstand the pick, and prospect holes have been sunk into this formation 
under the impression that the material belonged to the stream deposits. These 
rocks are folded, but otherwise are little changed. 
