Upper Helderberg Group. 459 



DlPHYPHYLLUM BREVE, 11. Sp. 



Corallum simple, short, turbinate ; posterior side straight, anterior 

 curved, length respectively 8 and 10 mm.; calix 18 mm. in diameter, 

 depth 4 mm., slightly oval, sides descending more or less abruptly; 

 fosse tte prominent, situated anteriorly; number of lamellse from 60 to 

 70, alternating in size, broad and rounded near the margin, becoming 

 thinner as they approach the center; denticulations very prominent; 

 transverse section of inclosed internal area oval, length 4 mm., width 

 3 mm. 



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



DlPHYPHYLLUM TUMIDULUM, 11. sp. 



Corallum small, simple, increasing by calicular gemmation ; length 

 15 mm. or less, from 3 to 4 mm. in diameter for about one-half the 

 length, then quite abruptly expanding ; diameter of the calix from 

 7 to 10 mm., depth 5 mm.; number of lamella 50, alternating in size ; 

 denticulations prominent; inclosed internal area 1 m. in diameter. 



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



CYSTIPHYLLUM, Lohsdale. 



Cystiphyllum bipartittjm, n. sp. 



Corallum simple, turbinate or sub-cylindrical, elongate; exterior 

 with narrow, slightly elevated annulations and concentric stride ; exter- 

 nal costae obscure ; calix oval, oblique, with a strong rounded ele- 

 vation extending from the bottom to the anterior margin ; somewhat 

 coarse rudimentary rays converging to the ridge and bottom of 

 calix and obscuring the cysts, which, near the margin, are small, 

 becoming larger near the center; height of large specimen 100 mm.; 

 diameter of calix 35 mm. 



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



* 

 Cystiphyllum bifurcatum, n. sp. 



Corallum simple, turbinate, regularly curved ; exterior with frequent 

 rounded annulations ; when decorticated the internal costse are distinct ; 

 calix nearly circular, oblique ; fossette pyriform, situated posteriorly, 

 a slight ridge marking its continuation on the anterior side of the 

 calix ; near the margin there are nine rudimentary lamellse in the space 

 of 5 mm.; as they approach the center two adjacent lamellae usually 

 coalesce, forming one larger one ; cysts moderately large, obsolete in 

 bottom of calix; height of corallum 70 mm., diameter of calix 30 mm. 



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



