204 PALEONTOLOGY OF OHIO. 



mens, however, these secondary calices appear to be absent, and then the 

 species is recognizable by its large, oval, thin- walled calices, arranged in 

 diagonal rows, and separated by minute tubuli, its smooth surface, and 

 its small dimensions. Whether the appearance of secondary calices is 

 due to the formation of perforated diaphragms over the mouth of the 

 tubes at their final period of growth or not, I am not prepared to say. 



Posttion and locality : Cincinnati group, Cincinnati, Ohio. From the collection of 

 Mr. U. P. James. 



Chetetes petropolitanus, Pander. 



Plate 21, figs. 14-146. 



Favosites pelropoUtanus, Pander; Russ. Reiche, pi. I, figs. 6, 7, 10, 11 (1830). 



Calarnopora fibros(4 {-pa,rfi), Goldf. ; Petref., pi. 64, fig. 9. 



Favosites henmplierkus, St. Kutorga; Zweit. Beitr. znr Geogn. and Palteont., pi. S, fig. 5, 



and pi. 9, fig. 3. 

 Calamopor a fibrosa, Eichwald ; Sil. Syst. in Esthl., p. 197. 



Favosites lycopoditps, Lardner Vanuxem ; Geol. of New York, 3d Part, p. 46, fig. 3. 

 Chietetes petrpoUtanus, Lonsdale, in Murch. Vern. and Keys; Russ. and Ural., Vol. I., 



p. 596. pi. A, fig. 10. 

 Favosites 2)e^ropolitana, McCoy; Syn. of the Silur. Foss. of Ireland, p. 64, pi. 4, fig. 21. 

 Chsetetes lycoperdon, Hall (pars) ; Pal. N. Y., Vol. I., p. 64, pi. 23, fig. 1, and pi. 24, 



figs, la-/; Vol. II., p. 40, pi. 17, figs. la-f. 

 Chxteles rugosus, Hall ; Pal. N. Y., Vol. I., pi. 24, fig. 2. 

 Chsetetes petropolitanus, lycoperdon, and sub-fibrosus, D'Orbigny ; Prodr. de Palcont., Vol. 



I., pp. 25 and 108. 

 Chietetes petropolitanus, Edwards and Haime, Pol. Foss. des Terr. Palseoz , p. 263. 

 Monticidipora petropolilana, Edwards and Haime, Brit. Foss. Corals, p. 264. 

 Chsetetes petropolitanus f. Meek and Worthen; Geology of Illinois, Vol. III., p. 304, pi. 



2, fig. 8 a, b. 



"Corallum in general free; its basal plate flat or concave, and com- 

 pletely covered with a thin concentrically wrinkled epitheca. Upper 

 surface regularly convex, in general hemispherical, and presenting ob- 

 tuse tuberosities, about one line broad and varying very much in height. 

 In some specimens these tubercles appear to have worn away, and their 

 existence is indicated only by the presence of small groups of large 

 calices, with thick walls; the calices are rather unequal in size, gener- 

 ally polygonal, sometimes almost circular ; the largest are about one- 

 fifth of a line in diameter ; the walls are not perforated. The tabulae 

 are horizontal, complete, and placed about one-twelfth of a line from 

 each other. Some vestiges of septa are often visible. Young specimens 



