432 Thirty-fifth Keport ok the State Museum. 



with the tabulae and becoming obsolete, leaving a space at the center 

 5 mm. in diameter, which is smooth, or with the striae very faintly in- 

 dicated ; fossette distinct extending from flat space at the bottom of 

 calix to the exterior margin. 



Formation and locality. Schoharie grit, Albany county, N. Y. 



Zaphrentis subcompressa, n. sp.J*/ m x?.fty /*>*& 



Corallum simple, turbinate, curved, somewhat flattened ; exterior 

 with numerous sharp annulations of growth ; height of corallum 40 

 mm.; calix 30 mm. in diameter, broadly oval, depth 15 mm,, sides 

 abruptly descending, a slightly convex space at the bottom l-o mm. in 

 diameter ; fossette commencing a short distance from the center, and 

 extending about half-way to the anterior margin ; lamellae about 60 

 of nearly uniform size at the margin ; thickened and subangular on the 

 sides, becoming thinner and alternating in size below; the principal 

 lamellae extend to within 4 mm. of the center, for the last 3 mm. be- 

 coming thickened ; the central portion of the cup consists of a smooth flat 

 space 8 mm. in diameter. This species somewhat resembles Z. corru- 

 gata, but the lamellae are much thicker at the margin of the cup, and 

 of more nearly uniform size ; the central portion of the calix is smooth 

 and the lamellae are much thickened as they approach this area. 



Formation and locality. Oorniferous limestone. Falls of the Ohio. 



Zaphrentis Colletti, n. sp.Tlxf, FU $IV6< 



Corallum simple, turbinate, curved, near the base and for some dis- 

 tance above usually compressed ; calix circular ; exterior with strong 

 rounded ridges of growth, longitudinal striae prominent ; length of the 

 posterior side of an adult specimen 40 mm., of the anterior side 70 

 mm. ; diameter of the calix, 45 mm., sides gradually sloping, a space 

 at the bottom, 10 mm. in diameter, very slightly elevated, smooth, or 

 rugose from the contorted lamellae ; number of lamellae from 70 to 80, 

 of nearly uniform size at the margin, alternating below, the principal 

 ones extending to the elevated space at the bottom. In different indi- 

 viduals there is considerable variation in the appearance of the lamel- 

 lae, in several the smaller lamellae coalesce with the larger, forming 

 lamellae with thick rounded margins which continue in that condition 

 to the bottom of the calix. In others they are of nearly uniform size 

 at the margin, alternate ones becoming obsolete on the sides, leaving 

 the principal lamellae sharp. In others, on the posterior side, all the 

 lamellae extend to the flattened space at the bottom of the calix, that 

 side having a much finer appearance than the other. 



Formation and locality. Oorniferous limestone. Orab Orchard, 

 Kentucky. 



