312 PAL^ONTOLOOT OF NBW-YOEK. 



373. 27. ORTHOCERAS CORALLIFERUM { n. sp.) . 

 Pl. LXXXV. Fig. 3 ; and Pl. LXXXVI. Figs. 1 a, b, e, d. 



I have collected numerous fragments of Orthocerata, which, from being compressed 

 and denuded of tlie shell, or partially preserving the shell with its markings obliterated, 

 cannot be characterized with precision. Many of these are partially covered by some 

 incrusting coral, and as this circumstance is characteristic of specimens from widely 

 separated localities, it may be useful in identifying the species. 



The septa are closely arranged ; the tubes very gradually tapering and often attaining 

 a large size. The distance of the septa, as compared with the diameter of the shell, appears 

 to be variable, from the greater or less degree of pressure which it has suffered. 



Plate LXXXV. 



Fig. 3. A large specimen, extremely compressed, from the Utica slate. 



Plate LXXXVI. 



Fig. 1 a. A small fragment, from the altered shales near Waterford, Saratoga county. The septa are 

 represented too distant in the figure. A portion of the coral covering the surface is magnified 

 in fig. 1 b. 



Fig. 1 e. A fragment, from the green shales of Lewis county. 



Fig. 1 d. A fragment from the sandstone of the Hudson-river group. 



Position and locality. This species occurs in the Utica slate at Turin, and in the shales 

 and sandstones of the Hudson-river group at Turin, Boonville, Pulaski, Rome, and other 

 places. (State Collection.) 



374. 28. ORTHOCERAS LAMELLOSUM ( n. sp.). 

 Pl. LXXXVI. Figs. 2 a, b, c, d. 



Slender, very gradually tapering to an acute point; septa distant from one fifth to one 

 fourth of an inch, having a convexity about equal to their distance from each other ; 

 siphuncle slightly excentric ; surface apparently lamellose or subimbricate. 



This species is of frequent occurrence in the calcareous portions of the Hudson-river 

 group. It differs but little from Endoceras proteiforme, in the distance of septa and position 

 of siphuncle ; but the character of the shell appears to be quite distinct. 



Fig. 2 b, c. Fragments near the smaller extremity ; the septa being indistinctly preserved. 



Fig. 2 d. A fragment, showing the comparative distance of the septa, in which it varies slightly from 



fig. 2 6. 

 Fig. 2 e. Section of the last, showing the position of the siphuncle. 



Position and locality. This species occurs at Turin, Loraine, Pulaski, and near Rome, 



(State Collection.) 



