TRENTON LIMESTONE. 
223 
There is little difficulty in identifying this curious and beautiful fossil, which is quite 
abundant in the Trenton limestone. The obliquely transverse ridges and nearly vertical 
strife, which are always more prominent in the depressions than upon the ridges, are con¬ 
stant in a large number of specimens. The shell at the angles seems to be slightly folded 
inward, producing a groove, which interrupts the transverse ridges. It is but rarely that the 
septa and sipliuncle can be seen ; the latter is usually excentric, but in one specimen there 
is an obscure appearance of a duplicate siphuncle. When the outer lamina of the shell only 
is removed, the cast preserves the sharp transverse ridges, the longitudinal striaj being 
obliterated. The entire cast is smooth, with a deep groove at the angles, and a shallow 
one on the centre of each face of the pyramid. 
Fig. 1 a. A specimen (natural size), with the apex broken off. 
Fig. 1 b. Another specimen, more abruptly acute. 
Fig. 1 c. Transverse section of a, near the apex, showing the septum and siphuncle. 
Fig. 1 d , e. Lateral and transverse view of a fragment, showing the convex septum. 
Fig. 1 /. A portion of the surface enlarged. 
Position and locality. In the central and higher part of the Trenton limestone at Middle- 
ville, Jacksonburgh, Trenton Falls, and other places. 
288. 2. CONULARIA GRANULATA ( n. sp.). 
Pl. LIX. Fig. 2. 
Conical or pyramidal; specimen compressed, tapering rapidly to an acute point; angles 
marked by linear grooves or sulci; surface marked by distinct transverse striae, which are 
crossed by finer longitudinal ones, giving, under a magnifier, a granulated or papillose 
appearance to the shell; no septa or siphuncle visible. 
This species is quite distinctly marked; and from the examination of several specimens, 
I have no doubt of the propriety of its reference to the Genus Conularia. The specimen 
figured is in soft shaly limestone, and presents no more than a thin laminar expansion. It 
differs essentially from the last in the character of its markings, which are also much finer, 
being scarcely visible to the naked eye. The surface is marked by longitudinal lines or 
folds, which are probably due to the folding of the shell from pressure. 
Fig. 2 a. A specimen nearly entire, giving the general form of this species. 
Fig. 2 b. A portion of the surface enlarged. 
Position and locality. In the upper shaly portion of the Trenton limestone, associated 
with Lingula , Orbicula, §'c. 
289. 3. CONULARIA PAPILLATA (n. sp.). 
Pl. LIX. Figs. 3 a, b. 
Compare Conularia quadrisulcata, Dalman, Vet. Acad. Handlingar, 1824, pag. 374, pl. 4, fig. 3. 
Pyramidal, sulcated at the angles, gradually diminishing towards the apex; surface 
