106 [Senate 



GOMPHOCERAS (APIOCERAS) FISCHERI ( n.s.). 



Shell large, broadly clavate or elongate subovoid, attenuate below and yentricose 



above, somewhat abruptly contracted at the aperture. Septa closely arranged. 



Surface finely striated concentrically. 



The length of one specimen is seven inches, with a diameter of four inches in its 

 widest part, which is at a point three-fourths of an inch above the la.st septum : 

 from the last septum it tapers gradually to the apex, measuring eleven septa in the 

 space of three inches. It is a much larger and more ventricose shell than the pre- 

 ceding, but not so rotund or abruptly contracted at the aperture. It is a remarka- 

 bly large and fine species. 



Geological formation and locality. In the Goniatite limestone : at. Manlius, 

 Onondaga county, N.Y. 



GOMPHOCERAS (APIOCERAS) CONRADI ( n.s.). 



Shell small, clavate or fusiform, gradually enlarging from the apex to a little 

 below the aperture, where it is greatly constricted, or becomes gradually smaller 

 to the contraction of the aperture proper, the shell being folded abruptly in- 

 wards. Aperture transverse, occupying the greater part of the width of the 

 cavity at the summit; the sinus extending below the summit, and marked by a 

 few concentric wrinkles. Septa simple, rather deeply concave, about nine in the 

 space of five-eighths of an inch, the last one narrower than the others. The 

 diameters below the outer chamber measure respectively eight- and nine- 

 sixteenths of an inch, and the length of the outer chamber is half an inch. The 

 surface appears to have been longitudinally striated. 



From the same rock and same locality I have a fragment of a chambered shell, 

 which is marked by strong longitudinal rounded and somewhat distant striae; 

 which I am inclined to refer to the same genus, but which can scarcely be the 

 same species. 



In several species of this genus, I have observed that those with longitudinal' 

 striae are but little expanded at the outer chamber, and sometimes contracted to- 

 wards the extremity, and truncate rather than rounded at the aperture; while the 

 concentrically striate species are more ventricose in the outer chamber. Should 

 these characters be found constant, it may be necessary to refer the species to two 

 genera, and reduce the present generic synonimy. 



Geological formation and locality. In the Goniatite limestone at Manlius, N.Y. 



ORTHOCERAS MARCELLENSIS (Yanuxem). 



( Orthoceras typus : SiEsrAXN, loc. cit.) 



Shell extremely elongate, straight; section circular, gradually tapering to an 

 extremely minute apex, and, in its greatest width at the aperture, measuring 

 about two inches : the diameter is about equal to the extent of three septa next 

 below the point of measurement. Septa deeply concave, the concavity equal to 

 three-fourths their distance apart, slightly bending downward on the dorsal 

 side, and a little arched on the* opposite side. Siphuncle small, subcentral. 

 Surface marked by fine closely arranged concentric stride, with a longitudinal 

 suture line on the ventral side. 

 Geological formation and locality. This species is abundant in the Goniatite 



limestone, at Manlius and Marcellus, and less common at Schoharie. 



