27. CONTRIBUTION TO 



Number of lamellse fifty-eight, in the circumference of a calix, fifteen millimeters 

 in diameter, rounded and equal in size at the margin, alternating below, rapidly 

 sloping to the bottom of the calix, where the short ones graduall}'- terminate ; 

 the longer ones continue to the margin of the vertical wall in the bottom of the 

 calix, and abruptly end. Denticulations fine, ten in the space of seven 

 millimeters. Fossette in some of the cups obscure ; when visible, it consists 

 of a slight depression at the edge of the horse-shoe shaped area, but does not 

 extend on the side of the calix. 



Found in the upper Devonian (Hamilton group), near Charlestown, Indi- 

 ana. Now in the collection of the author, 



DIPHYPHYLLUM PROLATUM, N. Sp. 



Plate 11. Fig. 1. 



Corallum composite, rapidly increasing, by both lateral, and calicular gem- 

 mation, growing rather loose, corallites never very much crowded. There is a 

 broad scar at the base of attachment of the parent cup. Height of the longest 

 corallites two and one-half inches. Diameter of calyx from eight to eighteen 

 millimeters. Depth five to ten millimeters, with a smooth, horse-shoe shaped 

 area, surrounded by a vertical wall in the center of the calix, two millimeters 

 in diameter. Number of lamella?, forty-six, in the circumference of a calix fif- 

 teen millimeeers in diameter, equal, or in some cups, slightly unequal at the 

 margin, alternating below, for two or three millimeters from the margin, 

 nearly flat, then abruptly slope to the bottom of the calix, where the short ones 

 terminate. The longer ones continue to the vertical wall in the center of the 

 calix, and abruptly end. Denticulations fine, sharp ; seven in the space of four 

 millimeters. 



The loose spreading stems, and the lateral and calicular manner of increas- 

 ing, makes this easily recognized from all other species. 



Found in the upper Devonian (Hamilton group), near C-harlestown, Indi- 

 ana. Now in the collection of the author. 



DIPHYPHYLLUM A D J U N C T U M, N. Sp. 



Plate 12. Fig. 1. 



Corallum solid, rather large, composite, rapidly increasing by lateral gem- 

 mation. Corallites unequal in size, from five to fifteen millimeters in diameter, 

 intimately connected throughout their length. Calix broadly bell-shaped. 

 Number of lamellje, forty-five in a calix, fifteen millimeters in diameter. A 



