FOSSILS OF THF CLINTON GROUP. 521 



Orthis biforata. 



Ortliis elegantula. 



Orthis circula occurs possibly also in Ohio, but the identification is not altogether 



satisfactory. 

 Meristella umbonata finds its nearest relatives with Clinton forms in New York. 

 Atrypa marginalis seems to be identical with A. plicatula, but there is need of 



actual comparison with the types of the New York species. 

 Rhynchonella scobina is closely related to Rh. neglecta. 

 Phylloporina angulata. 



Phcenopora platyphylla, is almost certainly Ph. constellata. 

 Rhinopora verrucosa, including also the form Rh. ttibulosa. 

 Fa z 'o sites favoso ideas. 

 Halysites catenulatus. 



In the following pages it has not been attempted to make either the 

 list of fossils or the description of the same complete. The writer has 

 simply used such material as was available at the time of writing, there 

 being no satisfactory library at command, and even his private collections 

 not being all at hand, when needed, various portions of this report hav- 

 ing been prepared at different places as time would permit. It is hoped i 

 however, that even in its present state it may serve as a contribution to 

 the rather small list of Clinton literature. The full description of the bra- 

 chiopod forms was prepared for the reason that in the Ohio Clinton it is rare 

 to find interiors or hinge areas, except of a few species, and it was consid- 

 ered desirable for purposes of phylogenetic study to have minute descrip- 

 tions at least of that part of Clinton brachiopod forms which was known 

 in order to compare the same with better known Niagara material. In 

 the case of trilobites, cephalopods, gasteropods, and lamellibranchs, where- 

 ever there was no new material to offer, the descriptions were made as 

 brief as possible, calling attention only to the most important character- 

 istics. No description is provided in the case of bryozoans and corals, 

 excepting where changes of nomenclature or the addition of a new form 

 to the list of previously known species has rendered a description im- 

 perative. By this means it has been possible to offer a certain amount of 

 new material, and to keep the chapter within certain bound.?, prescribed 

 to the same. Acknowledgments for information and use of specimens 

 are made as far as possible at the appropriate points in the text. 



