68 



Cincinnati Society of Natural History. 



41. — M. cleavelandi James, 1882. 



Corallum lobate or amorphous, with flattened or cylindrical 

 branches; surface with rounded monticules, more or less conspicuous, 

 about one line apart, occupied by calices larger than in other places ; 

 calices polygonal or sub-circular ; no interstitial pores at the surface ; 

 walls of corallites in the axial region very thin and tortuous, the tubes 

 inclining gently outward and opening in a slightly oblique direction ; 

 tabular complete and numerous, more closely set near the surface than 

 in the axial region, direct, curved or oblique; corallites polygonal; 

 spiniform corallites somewhat angular. (The Paleontol., No. 6, Sept. 

 1882, p. 47.) 



Locality. — Highland county, O. 



42. — M. dawsoni Nicholson, 1881. 



Corallum irregularly lobate or frondose, forming an undulated 

 expansion of variable size, about two lines thick ; surface with numerous 

 close-set, prominent monticules, markedly elongated, about a line or 

 less apart, and occupied by corallites not differing conspicuously in 

 size from those forming the mass of the corallum ; calices polygonal, 

 thin walled, nearly vertical from a central axis, and opening on either 

 side : no regular series of small apertures, but occasionally a few 

 spiniform corallites at angles of junction of cells; walls delicate, 

 wrinkled, slightly thickened toward mouths of cells ; corallites vertical 

 and bending outward to the surface with a very gradual inclination ; 

 in the axial region with thin, wavy or undulated walls, which become 

 thickened in the cortical region ; tabulae wanting in the axial but 

 moderately developed in the cortical region, complete and horizontal 

 and about the same in number in both large and small corallites ; 

 tangential sections show only one series of corallites, approximately of 

 the same size, polygonal; occasional interstitial corallites, but numer- 

 ous minute, circular, thick-walled spiniform corallites. (Genus Montic, 

 1 88 1, p. 141.) 



Locality. — Warren and Clinton counties, Ohio. Rare at Cincin- 

 nati. 



Remarks. — This is similar to M. mammulata, but differs in the 

 more prominent, elongated and closely set monticules. 



43.— M. molesta Nicholson, 1881. 

 Corallum usually frondescent, forming extended and undulated, 

 lobed or palmate expansions, varying in thickness from two to five 



