22. CONTRIBUTION TO 



sixty millimeters. Calix broadly campanulate, thirty-five millimeters in diame- 

 ter. Depth twenty millimeters. "With a flat space in the bottom of the calix 

 occupied by the tabula), twenty millimeters in diameter. Number of lamellse 

 sixty-two, in the circumference of calix, thirty-five millimeters in diameter, 

 somewhat equal in size and broadly rounded at the margin, alternating below, 

 for about five millimeters gradually, then rapidly slope to the bottom of the 

 calix, where the short one terminate. The longer ones become slightly elevated 

 and thinner as they approach the bottom of the calix. On reaching the bottom 

 they abruptly become thiner and smaller and are only faintly indicated in the 

 center of the calix, in some examples the lamelhe does not extend to the cen- 

 ter of the cup, leaving a smooth space in the bottom five or six millimeters 

 in diameter Exterior with shallow, distant annulations, and wrinkles, caused 

 by intermittent growth. Fossette consists of a deep depression on the sinistral 

 side of the tabuJjc, but does not extend on the side of the cup. On the dex- 

 tral side of the calix there is one principal lamelho, slightly elevated above the 

 others, that extends to the center of the calix, and in some examples it extends 

 to the margin of the fossette, and abruptly ends. 



Found by Mr. John Sellers, in w^hose honor the specific name is given, in 

 the upper Devonian (Hamilton group), at Speed's Quarrj'-, Clark County, In- 

 diana. Now in the collection of the author. 



ZAPHRENTIS OBLIQUATUS, N. Sp, 



Plate 8, Fig. 1-2-3. 



Corallum simple, elongate turbinate, regular or irregularly curved, or dis- 

 torted. Acute at the base of attachment, gradually increasing in diameter to 

 the calix. Height of an adult specimen ninety millimeters. Diameter of calix 

 twenty-five millimeters. Depth twenty-five millimeters. Walls very thin and 

 vertical. Number of lamellae, seventy in the circumference of a calix, twenty- 

 five millimeters in diameter, unequal in size at the margin, alternating below, 

 the short ones scarcely more than rudamentary, the longer ones continue to the 

 bottom of the calix, and abruptly terminate. Tabulae oblique, very thin, occu- 

 pies the entire diameter of the corallum. Fossette consists of a slight depres- 

 sion, at the dextral margin of the tabular, but does not extend on the side of the 

 coral. Exterior with deep constrictions, and wrinkles, caused by intermittent 

 growth. 



The very thin deep calix, and broad oblique tabulae, deep constrictions, and 

 wrinkles, makes this easily recognized from all other species. 



Found in the middle Devonian (upper Helderberg group), at the Falls of the 

 Ohio. Now in the collection of the author. 



