378 Proceedings of Ihe Oliio State Academy of Science. 



1805. Spirit era Rocliymontana? Whitfield, Geol. Surv. Ohio, Vol. VII, 

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

 Maxville limestone : Newtonville, Ohio. 

 1895. Spirifer l^colciilc. Hall and Clarke, Pal. N. Y., Vol. VIII, pt. 2, 

 pi. 80, figs. 21-24. 

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

 1895. Spirifer l^eol^iilc var. ? Hall and Clarke, Pal. N. Y., Vol. VIIT, 

 pt. II, pi. 37, figs. 13-15. 

 St Louis group: Southern Indiana? 

 1897. Spirifer l^eol^nl^. Weller, Trans. N. Y. Acad. Sci., Vol. XVI, p. 

 257, pi. 19, figs. 10-12. 

 Batesville sandstone : Batesville, Arkansas. 

 1909. Spirifer t^eolml;. Grabau and Shimer, N. A. Index Foss., p. 333, 

 fig. 425 a, b. 

 Keokuk : Ohio, Illinois, Iowa, Utah. 



"Spirifcra Rockyinontanaf 



Plate IX, fig. 20. 

 ^'Spirifcra Rockynwntana Marcou. Geol. N. Amer., p. 50, pi. 7, 



%. 4. Feb. 1858. 

 ^'Spirifcra keoknk liall, Geol. Rept. Iowa, Vol. I, pt. 2, p. 642, 



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

 "Spirifera keoknk \'ar. Hall. Ibid., p. 672, pi. 24. fig. 4. 

 "Spirifera opinia Hall, Ibid., p. 71 1. pi. 28, fig. i. 



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

 S. keoknk var. Prof. Hall, have been obtained from Newton- 

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

 Louis and Chester limestones of Iowa, as to be absolutely indis- 

 tinguishable ; the form of the shell, the form and number of the 

 plications, and the minute surface structiu'e 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 simple, 

 rounded, or sub-angular plications on each side, and from four 

 to six bifurcating or dividing plications on the fold and sinus. 



