216 
PALAEONTOLOGY OF NEW YORE. 
abruptly bent forward in the centre, but absolutely continuous, though more 
frequently alternating and interlocking, while often there is no visible departure 
from a regular curving line. 
The ornamentation upon the crests of the strise and the upper half of the 
interstriate spaces is precisely the same as already described; but the strise are 
stronger. The specimen has a much coarser and stronger aspect than any 
other one observed, and the pyramid is more abruptly expanded from the 
apex. The single specimen known does not afford satisfactory evidence of 
specific distinction, and I have therefore recorded it as a variety of the form 
with which it preserves many characters in common. 
Formation and locality. In the coarse arnenaceous shales of the Hamilton 
group in Schoharie county, N. Y. 
The conditions of preservation in nearly all the species of Conularia are such • 
as to preclude any satisfactory determination of the angle subtended by the 
sides of the pyramid. The specimens have, in nearly every case, been more 
or less distorted by pressure, and more frequently completely flattened, so 
that the original form is never fully preserved. In these conditions the 
measurement of the apical angle is attended with difficulty, and the results are 
far from satisfactory. 
The following species have been carefully measured, and the angle given is 
the sum of the angles of two adjacent faces—the result corresponding to the 
angle inclosed between the edges of a flattened specimen. By this mode of 
measurement C. andulata , in several individuals, gives a range of 21° to 30°, 
and an average of 25°; C. crebristriata, 20° to 29°, and an average of 24^° 
in two individuals; C. Cayuga gives an angle of 28°; C. continens ranges from 
28° to 41°, and in four measurements gives an average of 35°; C. congregata, 
in four measurements, gives a range of 22° to 29°, and an average of 26°. 
These variations of the included angle are probably due, in a great degree, to 
the varying direction of the pressure which has flattened the shell; it rarely 
happening that this force is exerted in a vertical direction upon the face or 
upon the angle of the shell, but upon some intermediate point or in an oblique 
direction. 
