378 rroiccdiiHis of ihc Ohio Sliitc' .Icadciny of Science. 



18'.^'). Spirifera Rockyiiioiitaiia .' W hitl'ielcl, (ieol. Surv. Ohio, \'ol. VII, 

 p. 471, pi. 9, fig. 20. 

 Maxville limestone : Xewtonville, Ohio. 

 1895. Spirifer keokuk. Hall and Clarke, Pal. X. Y., Vol. VI II, pt. 2, 

 pi. 30, figs. 21-24. 

 Keokuk group : Keokuk, Lizard Creek and Marion County, Iowa. 

 1895. Spirifer keokuk var. ? Hall and Clarke, Pal. X. Y., Vol. VIII, 

 pt. II, pi. 87, figs. 13-lV 

 St Louis group: Southern Indiana? 

 1897. Spirifer keokuk. Weller, Trans. X. Y. Acad. Sci., Vol. XVI, p. 

 257, pi. 19, figs, ln-12. 

 Batesville sandstone : Batesville, Arkansas. 

 1909. Spirifer keokuk. Grabau and Shimer, X^. A. Index Foss.. p. 333, 

 fig. 425 a, b. 

 Keokuk: Ohio, Illinois, Iowa, Utah. 



"Spirifcra RockyniontaiiaF 



Plate IX. fig. 20. 

 ^'Spirifcra Rockxinoiitaiia Marcou. ( ieol. X'. Amer.. ]). 50, pi. 7, 



fig. 4. Feb. 1858. 

 ^'Spirifcra keokuk Hall. Geol. Rept. Iowa. \'ol. I. pt. 2, p. 642, 



pi. 20. fig. 3. Sept. 1858. 

 ^'Spirifcra keokuk \'ar. Hall. Ibid. p. 672, pi. 24. fig. 4. 

 "Spirifera opinio Hall, Ibid., ]). 711, pi. 28, fig. i. 



"Several specimens of a Spirifcra, of the form referred to 

 S. keokuk var. Prof. Hall, have been obtained from X'^ewton- 

 ville. CJhio. which are so entirely similar to those from the St. 

 Lotiis and Chester limestones of Iowa, as to be absoltiteh' indis- 

 tingtiishable ; the form of the .shell, the form and number of the 

 ])lications, and the mintite surface structure being exactly as in 

 those. 



"The form of the shell will vary from longer than wide to 

 much wider than long, dependent on the extension of the hinge 

 line. In profile the shell is extremely ventricose. with a strongly 

 enrolled beak ; a moderate cardinal area, vertically striated ; a 

 well-marked mesial fold and sinus ; from seven to ten sim])le, 

 roimded, or sul)-angular ])lications on each side, and from four 

 to si.\ l)ifurcating or dividing ]ilications on the fold anrj ■>inus. 



