350 University Geological Survey of Kansas. 
ina robusta (Stev.)?. About twenty-five species seem to be 
found here for the last time, among which are such species 
Dielasma bovidens Mort., Stenopora carbonaria (Worth.), 
Rhipidomella pecosi (Marc.), Pugnax utah (Mare.), Bairdia 
beedia U. and B., Modiola subelliptica Meek, ete. Productus 
nebraskensis Owen and Thamniscus octonarius Ulr. culminate 
here and are found in very great numbers, especially in the 
southern region. Pleurophorus subcostatus M. and W., Mya- 
lina kansasensis Shum., Derbya multistriata (Meek) and 
Schizodus sp. are of numerical importance here for the first 
time. 
The characteristics of this stage are the abundance of ostra- 
ecods and Strophalosia sp., the culmination of Productus nebras- 
kensis Owen and Thamniscus octonarius Ulr., the abundance 
of Derbya multistriata in the upper part of the section in the 
southern region, and the other species mentioned above. It is 
in the Neosho that the so-called Permian vertebrates occur, in 
a layer of blue clay about fifty or sixty feet below the top of 
the formation. These species are given at the end of the 
systematic list. 
In some instances the occurrence of the fossils given in this 
discussion is known to be too limited, but it is deamed better 
to give and discuss the data as we have it and omit the rest 
rather than to include hypothetical data with the known. 
Aside from the data given in discussing the faunal divisions 
above there are other features not discussed, such, for instance, 
as the horizons at which the dominating species are reduced to 
the ranks of the moderately common to rare species. This is 
an important class of evidence tending to the same results as 
that given, and can readily be noted on the chart. 
Range of Species. 
The great stratigraphic range of the species of the Kansas 
Coal Measures fossils has frequently excited comment. The 
reason for this is that the brachiopods, the best-preserved and 
most abundant fossils of these rocks, are conspicuous and form 
the great bulk of superficial collections and a large part of any 
collections. Certain of them are very conspicuous and are 
found throughout nearly the whole succession of the rocks. 
Before the stratigraphy had been accurately worked out and 
collections carefully labeled as to locality and horizon it is little 
wonder that those who had to deal with the subject were in- 
