THE AGE OF ANTHRACOLITHIC ROCKS 719 
limestone, and fifteen during the rest of the stage. Nineteen of these 
fossils are among the best-known Pennsylvanian species, such, for 
instance, as Campophyllum torquium, Rhombo pora lepidodendroidea, 
Stenopora carbonaria, Chonetes verneulianus, Dielasma bovidens, 
Meekella_ striaticostata, Acanthipecten carboniferus, Aviculopecten 
occidentalis, Schizodus wheelert, Euomphalus catilloides, and Taino- 
ceras occidentale. One of the peculiarities of this stage is the occur- 
rence of Chaetetes reefs, especially in the upper Fort Scott limestone. 
Another characteristic is the appearance of Foraminifera with the 
form of Fusulina, but with imperforate shells, probably belonging to 
the genus Fusulinella. These conditions maintain themselves until 
the close of the stage. 
These two stages combined make up a definite faunal unit of 
a larger order which I have designated as “Series I.’”’ Fusulinella 
and Chonetes mesolobus are confined to it, and Marginifera muricata 
is never so abundant again. Chaetetes milleparaceous is comparatively 
rare in the rocks above. 
The early part of Stage C is marked by another great influx of 
species which is more continued than that of the preceding stage, 
though the species are hardly as important. It seems very probable 
that at this time there was quite as general a sea connection between 
the Kansas sea and the rest of the world as at any time during the 
history of the basin. Such important species as Lima retijera, 
Sedgwickia granosum, and Orbiculoidea convexa are among those 
introduced—over thirty species in all. 
Stage D is the most striking horizon in the Kansas succession. 
Odlitic conditions with their accompanying fauna invaded the region 
and give us a peculiar assemblage of fossils, some of which seem 
quite foreign to their surroundings. We have in the Drum lime- 
stone, or its equivalent, at Kansas City and vicinity, a well-developed 
Pseudomonotis fauna. These fossils usually characterize the Per- 
mian rocks of Europe. They are here found in rocks far below the 
Permian. Unlike the faunas of the rocks above and below, this fauna 
is strongly molluscan. Many of the species introduced disappeared 
with the muddying of the waters, while others returned intermittently, 
especially the species of Pseudomonotis which became very prominent 
in the Permian rocks. 
