Upper Helderberg Group. 437 



Zaphrentis calcariformis, n. sp. 



Coralluin simple, narrowly turbinate, regularly curved ; diameter of 

 calices of individuals of the same height varying from 10 to 15 mm.; 

 exterior with frequent undulations aud low rounded annulations ; 

 height 25 mm.; fossette narrow, very deep, commencing at the center 

 and continuing to the posterior margin ; the lamellae extending to its 

 margin coalescing and forming vertical walls ; number of lamellae 50, 

 alternating in size ; at a distance of 2 mm. from the margin the smaller 

 lamellae coalesce with the others. This species is easily distinguished 

 by the deep, narrow fossette situated on the anterior side, and the reg- 

 ular coalescing of the lamellae at a short distance from its margin. 



Formation and locality. Corniferous limestone, Falls of the Ohio. 



'Zaphrejstis constricta, n. sp. 



Corallum simple, turbinate, straight or slightly curved; exterior with 

 frequent, sharp, narrow constrictions, giving to the corallum an invagi- 

 nated appearance; external striae very fine, distinct; height of coral - 

 um 50 mm., diameter of calix 35 mm., depth 20 mm., sides nearly ver- 

 tical, tabulae forming the floor of the calix, slightly convex, 20 mm. in 

 diameter ; fossette consisting of a deep depression at the dextral mar- 

 gin of the tabulae, not extending on the sides of the calix ; number of 

 lamellae 170, alternating in size, the smaller ones merely rudimentary, 

 becoming obsolete at a very short distance below the margin ; at equal 

 distances from the fossette, on each side, are two lamellae extending 

 from the margin to the center, the adjacent lamellae on each side 

 converging to them ; with this exception the lamellae extend upon 

 the flattened space at the bottom of the cup, many of them continuing 

 to the center, coalescing and forming a narrow, curving crest. This 

 species may be distinguished by the very fine lamellae at the 

 margin. 



Formation and locality. Corniferous limestone, near Louisville, 

 Kentucky- 



Zaphresttis ankulata, n. sp. 



Corallum simple, elongate turbinate, sometimes gradually and reg- 

 ularly, at other times abruply curving, so that one portion is at right 

 angles to the other ; exterior with strong annulations, which are fre- 

 quently at quite regular distances apart, and numerous moderately 

 strong concentric striae ; tabulae usually flat, curving downward toward 

 the margin, extending nearly the entire diameter of the corallum ; 

 number of lamellae 120, the smaller ones rudimentary. 



Formation and localities. Corniferous limestone, Falls of the Ohio 

 and Charlestown, Indiana. 



