142 Thirty-second Report on the State Museum, 



STREPTELASMA, Hall. 

 Streptelasma stricta. 



(PLATE I, FIGS. 1-10.) 



Streptelasma (Petraia) stricta, Hall. Twenty-sixth Rep. N. Y. State Museum of 

 Nat. Hist., p. 114. 1874. 



ZAPHRENTIS, Raf. 

 Zaphrentis Rcemeri. 



(PLATE I, PIGS. 11-21.) 



Zaphrentis Mcemeri, Edwards & Haime. Monog". des Polypiers Fossiles. Paris. 1851. 



AULOPORA, Gold/. 



AULOPORA ScHOHARLE. 



(PLATE II, FIGS. 1-6.) 



Aulopora tSchoharice, Hall. Twenty-sixth Rep. N. Y. State Mus. Nat. Hist., 



p. 110. 1874. 



Corallum consisting of elongate, tubular cells, gradually enlarging to the 

 aperture, transversely corrugated, longitudinally striated ; increasing sometimes 

 by one tube budding in a direct line from the basal part of another ; at others two 

 buds rising at an angle of about 45° from the parent tube. All the tubes, after 

 budding, assume an erect position and cease growth. Diameter of cell-tubes, at 

 apertures, a little more than one mm. ; length from five to seven mm. 



This species is much smaller than that in the Hamilton group referred to A. 

 tubceformis Goldf. ; it corresponds more nearly in size to A. serpens var. minor 

 Groldf., in Petref. Germ., p. 82, pi. 29, fig. 16, but is larger than that figure ; 

 the extremities of the tubes are more unequal, and the mode of growth and 

 bifurcations differ. 



Formation and localities. In the shaly limestone of the Lower Helderberg 

 group, at Schoharie and near C larks ville, N. Y. 



Aulopora tubula, n. sp. 



(PLATE II, FIGS. 7, 8.) 



Corallum consisting of comparatively short, tubular cylindrical cells, gradually 

 increasing in size to the aperture ; generally two buds from each cell, sometimes 

 three, two laterally and one from the basal portion nearer to the aperture ; 

 showing spinules in the interior ; transversely corrugated and strongly striated 

 longitudinally ; growing in close aggregation from the rapid and repeated bud- 

 ding. Length of cell-tubes about two mm. ; diameter at the apertures a little 

 more than one mm. ; diameter at the base nearly one mm. 



This species differs from A. Schoharice in its shorter tubes and proportionally 

 greater diameter, its more frequent gemmation and closer aggregation of growth. 



Formation and locality. In the shaly limestones of the Lower Helderberg 

 group, Schoharie, N. Y. 



