LOWER HELDERBERG ROCKS. 
:*»5 
Platyceras elongatuiii (n.s.). 
Plate LXIV. Fig. 6 & 10. 
Shell elongate-conical, straight or slightly bent near the apex, which is 
central or subcentral : aperture somewhat rounded. 
Surface cancellated by undulating transverse lamellose striae and lon¬ 
gitudinal rounded striae, which, in the partially worn surfaces, are of 
nearly equal strength. One or two longitudinal undulations mark the 
surface, but there are no distinct plications. 
This species is much more elongated and more nearly straight than the preceding 
one, and the surface is free from distinct plications. 
Fig. 6. A young specimen of this species. 
Fig. 10. A large individual from which the extremity of the apex is broken, and the shell 
partially exfoliated from the lower part. 
Geological position and, locality. In the shaly limestone : Schoharie county. 
Platyceras elongation? var. 
Plate LXV. Fig. 5 a, b. 
Shell slightly arcuate, tapering very gradually above, with a few obscure 
undulations towards the base. 
Surface cancellated by transverse and longitudinal strim. 
The specimen figured, with another of similar character, present some deviations 
from the specimen fig. 10, Plate lxiv, and appear never to have been so extremely 
elongated, and are also a little curved, while that one is rigidly straight except near 
the apex. 
Fig. 5 a. A fragment of a specimen, natural size. 
Fig. 5 b. An enlargement of the surface striae. 
Geological position and locality. In the upper part of the shaly limestone of the 
Lower Helderberg group : Schoharie county. 
