Twenhofel and Dunbar — Nodules ivith Fishes. 157 



Art. XI Y. — Nodules with Fishes from the Coal Measures 

 of Kansas ; by W. H. Twenhofel and Carl O.. Dunbar.* 



The rarity of vertebrate remains in rocks of Pennsylvanian 

 age makes each new discovery of great interest. The Ameri- 

 can localities where vertebrate fossils of this period occur 

 in sufficient completeness to be of value are so few that 

 they may almost be counted on the fingers of one's hand, 

 while in Kansas such have been among the rarest of fossils. 

 Two noted localities are Mazon Creek,. Illinois, and the mines 

 about Linton, Ohio. The former locality has long been 

 famous because of the excellent preservation of its plants, 

 Crustacea and insects, and the fossils possess an added interest 

 because of their occurrence in nodules. 



Kansas Nodule Horizons. 



Fossil-bearing nodules have also been collected in the Kansas 

 Coal Measures. The Labette shales, near Sherman City, carry 

 many, of which great numbers contain the brachiopod, Orbi- 

 culoidea nitida (Phillips). This fossil also occurs abundantly 

 in the nodules of the Cherokee shale. The LePoy shales have 

 nodules which are fossiliferous and others are also quite com- 

 mon in the Yilas shales, but of the many from the latter hori- 

 zon which have been broken open by the writers, not one has 

 contained anything of value. At Twin Mound, about ten 

 miles southwest of Lawrence, what appear to be the Kanwaka 

 shales carry great numbers of nodules. Doctor P. L. Moodie 

 has broken open hundreds from that locality and in only a 

 few was anything discovered. Local collectors, however, have 

 obtained one Or two specimens of Prestwichia dance. 



A New Nodule Horizon. 



To the localities and horizons noted abo-ve, another must be 

 added, which is of exceptional interest by reason of the remark- 

 able abundance and splendid preservation of the fish remains. 

 The discovery was accidentally made by the junior writer 

 while searching for Pennsylvanian invertebrates. An oblong- 

 gray nodule, which he carelessly cracked, contained a complete 

 and well-preserved skull. Naturally, invertebrates were neg- 

 lected and careful search was made for nodules. The first 

 afternoon's collecting netted three fish skulls and over a dozen 

 other bones. Since then the place has been repeatedly visited 

 and skulls have been found each time. 



* Published by permission of tbe Director of the Kansas Geological Survey. 



