Uppek Helderberg Group. 461 



Cystiphyllum latiradius, n. sp. 



Corallum simple, turbinate, straight or slightly curved, rapidly ex- 

 panding; exterior with gentle undulations and sharp constrictions; 

 when decorticated it presents a very distinctly invaginated appearance ; 

 height of corallum 60 mm.; calix broadly bell-shaped, diameter GO 

 mm., depth 20 mm., a flat space at the bottom about 10 mm. in di- 

 ameter occupied by large cysts ; near the margin are broad, gently 

 rounded rudimentary lamellae of nearly uniform size, 6 or 7 in the 

 space of 15 mm.; the cysts first appear at about 15 mm. from the mar- 

 gin, growing larger as they approach the center ; the broad plications 

 either end abruptly or are continued on the cysts as fine interrupted 

 striae. In a transverse section the corallum appears to be formed of 

 thin, superimposed laminae ; in the manner of growth and appearance 

 near the margin this species is very similar to a Chonophyllum. 



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



Cystiphyllum supraplanum, n. sp. 



Corallum simple, turbinate, proportional height and diameter vary- 

 ing in different individuals from 30 mm. in height and 30 mm. in di- 

 ameter at the calix, to 20 mm. in height and 40 mm. in diameter, the 

 corallum apparently consisting of thin, superimposed laminae; calix 

 superficial, 40 mm. in diameter, a flat, smooth space at the center of 

 6 mm. in diameter ; the sides for a short distance abruptly ascending, 

 then gently sloping to the margin ; number of lamellae 100 or more, 

 about one-half of them extending a short distance upon the flattened 

 space at the bottom of the calix. On the upper surface of the calix 

 the cysts are obsolete or indistinct, but on the under surface of the lam- 

 inae they are frequently quite distinct. 



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



Cystiphyllum crateriforme, n. sp. 



Corallum simple, turbinate, straight or curved; height of an adult 

 individual 70 mm., diameter of calix 50 mm., depth 40 mm.; on the 

 anterior side, commencing at the center and continuing to the mar- 

 gin, are two slight depressions, distant from each other, at the mar- 

 gin, 40 mm., the space between them nearly flat ; this feature in some 

 individuals is very distinct, in others more obscure ; no flattened space 

 at the center of the calix, the sides regularly and abruptly sloping to 

 the center; cysts small, from 1 to 3 mm. in diameter, most distinct 

 near the margin and center ; in other portions of the calix being ob- 

 scured by the rudimentary lamellae, which are continuous, closely 

 arranged and vary in number from 100 to 150. 



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



