202 Ciucinnati Society of Natural History. 



to about four lines in diameter ; surface smooth ; calices sub- 

 polygonal or rounded ; walls of corallites thickened ; inter- 

 stitial corallites numerous, angular, interspersed with the 

 ordinary corallites; corallites at first with thin walls, but 

 these becoming thickened in the outer part of their course, 

 the walls also seeminglj' becoming fused together ; spaces 

 between the corallites occupied by interstitial corallites, and 

 spiniform tubuli developed at the angles of junction of the 

 normal cells ; tabulse wanting or very sparingly developed in 

 the axial region, but more abundant in the outer zone; more 

 closely set in the small than in the large corallites, and com- 

 plete and horizontal in all cases. (Genus Montic, 1881, p. 

 131.) i^Chc^letes flctcheri Nicholson, Quart. Jour. Geol. Soc. 

 Ivond., vol. 30, 1874, p. 504; Dekayella obscura Ulrich, Jour. 

 Cin. Soc. Nat. Hist., vol. 6, 1883, p. 89.) 



Locality. — Cincinnati, O. 



Re?narks. — Externally this species is similar to M. andreivsii, 

 but that is generallj' more robust and has fewer interstitial 

 corallites. That form also shows maculae of corallites larger 

 than the average, while in the present species maculae, if 

 developed, are made up of smaller corallites than the average. 

 Mr. Ulrich's species, Dekayella obscura, presents too few 

 points of difference to be separated, and it is not necessary to 

 give them here. 



31. — M. GELASiNOSA Ulrich (sp.), 1890. 



Corallum dendroid, branches about 4 mm. in thickness ; 

 surface marked with conspicuous, elongated, parallel, dimple- 

 like macuke, arranged in tran.sverse rows ; calices sub- 

 angular, about ten in 2 min., those on the borders of the 

 maculce about one-half larger ; interstitial tubes angular, 

 comparatively large and shallow, occurring only in the 

 maculae ; walls of corallites thin, flexuous or wavy in the 

 axial region, moderately thickened near the surface; hori- 

 zontal and complete tabuUic occasionally present in the axial 

 region, but these changing to vesicles in the peripheral re- 

 gion ; spiniform tubuli at the angles of the corallites ; tubulae 

 in the small corallites horizontal and complete. (Geol. Sur. 

 Illinois, vol. 8, 1890, p. 410, as Homotrypa f^^elasiuosa.) 



Locality. — Wilmington, Ills. 



