INDIANA PALEONTOLOGY. 32 



ZAPHRENTIS NANUS, N. Sp. 



Plats 11. Figs. 2-3-4-5-6. 



Corallum simple, turbinate, straight or regularly curved. Acute at the 

 base of attachment, gradually or at times more rapidly expanding in diameter, 

 to the calix. Exterior with broad, irregular annulations, and shallow constric- 

 tions. Height twenty millimeters. Calix somewhat campanulat*, ten milli- 

 meters in diameter. Depth five millimeters: with a flat space in the bottom of 

 the cup. occupied by the tabulae. Six millimeters in diameter. Number of 

 lamellae, fifty-two, in the circumference of a calix, ten millimeters in diameter; 

 unequal in size at the margin, alternating in length, the short ones are scarcely 

 more than rudimentary ; the longer ones abruptly slope to within a short dis- 

 tance of the center, and terminate, leaving a smooth convex space in the bot- 

 tom of the calix, from two to three millimeters in diameter, No fossette visible 

 in any of the specimens examined. 



Superficially this has some 1-esemblance to Z. Acuticornis of Part 1, Plate 

 2, Figs. 9-10. But this species has no fossette, and the smooth convex space in 

 the center of the calix, is more pronounced in this species than in that. 



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

 ana. Now in the collection of the author. 



HELIOPHYLLUM JACKSONI, N. Sp. 



Plate 11. Figs. 7-8. 



Corallum simple, or compound. Acute at the base of attachment, Rap- 

 idly increasing in diameter to the margin of the calix. Exterior with strong 

 rounded annulations and constrictions. Height varying in diiferent examples 

 from twenty-five to forty millimeters. Calix broadly bell-shaped, from thirty 

 to thirty-five millimeters in diameter. Depth fifteen millimeters, with a flat 

 space in the bottom of the cup, occupied by the tabula\ ten millime- 

 ters in diameter. Number of lamellae sixty in the circumference of a calix» 

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

 from three to four millimeters from the margin, flat or slightly oval, then 

 gradually slope to the bottom of the calix, where the short ones terminate ; the 

 longer ones continue to the center of the calix, coalescing, and are slightly 

 elevated, not twisted. Denticulations course, irregular in position, from one 

 to two millimeters apart. Fossette conspicuous, commences near the center of 

 the calix, and continues to the anterior margin. 



