1896. ] NEW YORK ACADEMY OF SCIENCES. 205 
Horizon and Locality.—Fine gray shales of Div. 1 c., at Han- 
ford Brook, St. Martin’s, N. B., Canada. Rare. 
Other examples of this form show the apex to beacute. Bosses 
on the surface indicate that the transverse grooves of the inte- 
rior terminate near the dorsal margin in a cup-shaped enlarge- 
ment similar to that of S.triangularis, but no perforations of 
this margin have been detected. Both the dorsal and ventral 
zones of the shell are thickened, and the concentric ridges scarcely 
show there. 
STENOTHECA Hickstana. (Plate XIV., fig. 3.) 
Stenotheca Hicksiana, Trans. Roy. Soc. Can., vol. iii., pt. iv., 
p. 56, pl. vi., fig. 14. 
Amended description.—Conical, subtriangular, with strongly 
arched convex slope, and a concave slope which is strongly 
curved near the apex, but is straight for the lower two-thirds; 
the base is nearly straight for two-thirds of its length, but 
curves upward toward the convex slope; apex not known. 
The cone is compressed and carries on its side about two ridges 
on the concave side and five on the convex, owing to intercal- 
ation of additional ridges; perforations of the shell opposite 
some of these ridges, on the dorsal line. 
Size.—Height, 3 mm.; length of base, 33 mm. 
Horizon and Locality.—Dark grey shales of Div. 1. d. 1 at 
Porter’s Brook, St. Martin’s N. B., Canada. Rare. 
The comparatively few ridges ally this form with the succeed- 
ing ones. 
CIRRIPODITES n. gen. 
Small calcareous plates of peculiar contour and relief have 
from time to time been found in the beds which carry the 
remains of Eocystites; these plates are of such form that they 
do not appear to be of this genus, and the author has come to 
regard them as the covering plates of one or more species of 
Cirripedes. A symmetrical plate is rare among them, but they 
are usually characterized by one or more low keels with the 
surface somewhat depressed on one side of the keel and elevated 
on the other; many of them also have a deep furrow at one 
side, transverse to the keel. In their thickness and calcareous 
composition they resemble plates of Eocystites, to which some 
of them may belong. 
Complete skeleton unknown. The remains consist of small, 
thick, calcereous plates, usually asymmetrical in form, smooth, 
but having growth lines along the margin. The following are 
the chief variations in form : 
