99. CONTRIBUTION TO 



BORDENIA KNAPPI 



Plate 31. Figs. 4, 5, 6, 7, 8, 9, 10, 11. 



Zaphrentis deformis, Hall, Twelfth Annual Report of the Indiana Geologi- 

 cal Survey, 1882, page 290, plate 20, figures 9-10. 



Zaphrentis Knappi, Hall, Thirty-fifth Annual Report of the State of New 

 York, page 438, 1884. 



As the descriptions for both species are the same, I prefer the specifiic name 

 Knappi, as this was intend,ed as a compliment by Prof. Hall, to his old friend 

 Dr. James Knapp, of Louisville, Ky. 



Corallum simple, or composite, and sometime growing socially, two or more 

 together, with a broad scar at the point of attachment. Gradually, or some- 

 times more rapidly, expanding in diameter to the calix. Height varying in 

 different individuals, from fifteen to forty millimeters. Diameter of calix, from 

 ten to twenty-five millimeters. Depth, five to ten millimeters, with a smooth 

 space in the center of the calix, occupied by the tabula?, from ten to twelve mil- 

 limeters in diameter. Number of lamellae, from thirty to thirty-two, in the cir- 

 cumference of a calix, twenty-five millimeters in diameter. When well pre- 

 served they are unequal in size, and sharp at the margin, gradually descends to 

 the smooth space in the center of the calix, and abruptly terminates, leaving a 

 smooth space in the center of the cup, ten or twelve millimeters in diameter. 

 Secondary lamellae rudimentary. Fossette consists of a slight depression at the 

 margin of the smooth space in the center of the calix, but does not extend on 

 the side of the coral. Exterior with numerous strong rounded annulations and 

 wrinkles, caused by periodical growth. 



Found in the Upper Devonian (Hamilton group) at Charlestown, and in 

 the strippings above the difl'erent cement quarries, throughout Clark County^ 

 Indiana, now in my collection. 



GENN^:OCRINUS, FACETUS, N. Sp., (Rowley). 



Plate 32. Figs 1, 2, 3, 4, 5, 6. 



The body is low, basket shape, the ventral disk being hardly convex. 



The basals are three in number, and extend liorizontally outward beyond 

 the column base as three sharp ridges or tripartite rim. 



The first radials are hexagonal, each with a strong central tubercular 

 prominence, sharp and angular, extending outward almost horizontally and 

 overshadowing the basals. 



A sharp ridge extends upward from this tubercular prominence, fork- 

 ing on the third primary radial and each branch again dividing on a second 



