CORALS AND BRYOZOA. 
33 
CERAMOPORA, Hall. 1852. 
Ceramopora maculata. 
PLATE XVI, FIGS. 5-11. 
Ceramopora maculata , Hall. Twenty-sixth Rept. N. Y. State Mus. Nat. Hist., p. 106. 1874. 
“ “ “ Thirty-second Rept. N. Y. State Mas. Nat. Hist., p. 159. 1879. 
“ “ “ Report of State Geologist for 1882. Expl. pi. 16, figs. 5-11. 1883. 
Zoarium discoidal, flattened or concave on the lower side; base attached at 
the center to some foreign body, frequently a fragment of a crinoid stem or 
a small gastropod; the remaining portion free, covered by a strongly wrin¬ 
kled epitheca. Thickness of zoarium from 1 to 5 mm. Cells tubular, 
polygonal, arising from the epitheca, and radiating from the center, regularly 
curving to the surface; in the center being at right angles to the epitheca, 
and gradually becoming more oblique as they approach the margin. Apertures 
from .45 to .50 mm. in diameter, on some portions of the frond distinctly 
alternating and imbricating. There are slightly elevated circular monticules, 
the centers of which are distant about five mm., upon which the cells are 
slightly larger than on other portions. 
This species resembles C. imbricata of the Niagara limestone, but differs in 
the less distinctly cucullate apertures, it also grows to a much larger size. 
Formation and localities. Lower Helderberg group, Clarksville and Schoharie, 
N. Y. 
Ceramopora labeculoidea. 
PLATE XVI, FIGS. 1, 2. 
Ceramopora labeculoidea. Hall. Thirty-second Rept. N. Y. State Mas. Nat. Hist., p. 158. 1879. 
“ “ “ Report of State Geologist for 1882. Expl. pi. 16, figs. 1, 2. 1883. 
Zoarium consisting of very thin, circular, lamellate expansions. Under sur¬ 
face a concentrically wrinkled epitheca. Cells short, tubular, alternating, 
imbricating and oblique to the surface; more or less regularly radiating from 
the center to the margin of the expansion. Apertures arched or triangular, 
with two minute denticulations; width .33 mm. Surface marked by acellu¬ 
lar maculae; the apertures immediately adjacent to these are a little larger 
