SAGENOCRINIDAE 24/ 



The fact that in a prominent text-book of paleontology a widely different horizon is 

 given for this and several other species renders it advisable to append a more detailed state- 

 ment as to the geological position of the Richfield, Ohio, crinoids. The protracted contro- 

 versies relative to the Waverly Group of Ohio have given rise to some curious differences 

 of opinion as to the actual horizon of the crinoids from Richfield, Summit County, in north- 

 ern Ohio, described by Hall in the 17th Report of the New York State Cabinet of Natural 

 History, 1886, and afterward in volume 2 of the Paleontology of Ohio. At the time these 

 descriptions appeared, it was taken for granted that the specimens were derived from a 

 horizon approximating in a general way the Kinderhook of the Mississippi River region — 

 a formation which was considered by Hall, White, and the earlier geologists to be late 

 Devonian, equivalent to the Chemung of New York. Later, Meek and Worthen demon- 

 strated to the satisfaction of geologists generally the Carboniferous facies of this forma- 

 tion — a conclusion which was afterward strongly confirmed by Professor Calvin 1 in 

 connection with his discovery of an undoubted Devonian (probably Chemung) equivalent at 

 Lime Creek, Iowa, underlying the Kinderhook beds. 



The peculiar character of the crinoid fauna at Richfield was quite consistent with such 

 a geological position, and no one familiar with the stratigraphic range and distribution of the 

 crinoids saw any reason to doubt the correctness of the original interpretation. Hall himself 

 in his preliminary notice (17th Report, p. 51), after reviewing the evidence afforded by the 

 entire collection, said : " I should infer that the geological position of these species is between 

 the Hamilton Group and the Lower Carboniferous beds." When it was found, however, that 

 the term " Waverly " had been extended in Ohio to include a number of beds in central and 

 southern Ohio which were undoubted equivalents of the Burlington and Keokuk of Ohio 

 and Illinois, there was a disposition in some quarters to refer the Richfield crinoidal beds, 

 which are in part of a bluish grey color, to the Keokuk Group. This was done by Cooper in 

 1888 (Bull. Laboratory of Denison University, vol. 4, p. 123), who located them in the upper, 

 or Keokuk, subdivision of the Logan division of the Waverly. 



In 1891 Professor C. L. Herrick (Bull. Geol. Soc. America, vol. 2, pp. 31-48), as the 

 result of an extended and special field investigation, made a determination of the question 

 which ought to be conclusive. He showed that the crinoids from Richfield are derived from 

 a horizon of slow and uninterrupted transition from Devonian to Carboniferous — a period 

 of almost continuous sedimentation, wherein the disturbances " were neither violent nor 

 extensive enough to seriously interfere with the peaceful evolution of types " (p. 32) ; that 

 they occur in the Cuyahoga shales (p. 42) ; that he can " positively assert that the Cuyahoga 

 shale as represented in the northern tier of counties (Summit, etc.) is identical with that part 

 of the Waverly lying below Conglomerate I — i. e., below the undoubted actual equivalent of 

 the Kinderhook of central Ohio " (p. 37). And he adds on p. 36: " The work of the pres- 

 ent season has happily set the general question quite at rest, and will doubtless shed a flood 

 of light on the affinities of the crinoids of the Cuyahoga which have caused so much discus- 

 sion. Their curious resemblances to the Devonian species and the strange commingling of 

 Carboniferous characters can no longer be regarded as abnormal." 



Notwithstanding the evidence furnished by these investigations, and contrary to the 

 most palpable faunistic indications of the fossils themselves, S. A. Miller in the Second 

 Appendix to his North American Geology and Palaeontology, 1887, referred every one of 

 these Richfield crinoid species to the Keokuk Group; and afterwards in Bulletin 12 of the 

 Illinois State Museum, p. 11, it was stated by Miller and Gurley that the rocks of the Rich- 

 field crinoids " are now known to belong to the Keokuk." This involves the position of four 

 species of the Flexibilia. Of these " Forbesiocrinus" lobatus var. tardus is a clear survival 

 of a Devonian type, Dactylocrinus, while " F." communis, in part, represents the most primi- 

 tive type of Forbesiocrinus, in no way comparable to the mature forms of that genus found 



1 American Jour. Sci., June, 1883, p. 432. 



