CORALS AND BRYOZOA. 
289 
CLONOPORA, Hall. 1881. 
Clonopora fasciculata, n. sp. 
PLATE LXVI, FIGS. 1, 2. 
Zoarium simple or ramose, from 1 to 1.50 mm. in diameter. Cell tubes cylin¬ 
drical, of nearly uniform size tlieir entire length, diameter about .33 mm.; 
for two-thirds their length they are sub-parallel, diverging very gradually, 
then turning abruptly outward, they continue growth at an angle of about 
forty-five degrees to the axis of the zoarium. On one frond, which is appar¬ 
ently well preserved, the cells cease growth on turning outward. 
Formation and locality. Upper Helderberg group, Onondaga Valley, N. Y. 
Clonopora semireducta. 
PLATE LXVI, FIGS. 3, 4. 
Clonopora semireducta. Hall. Trans. Albany Institute, vol. x, abstract, p. 20. 1881. 
Zoarium ramose, branches generally consisting of an aggregation of cylindrical 
cell tubes, diameter about 1 mm.; cell tubes 2.50 in length, diameter .25 mm.; 
essentially parallel with the axis of the branch until within about 1 mm. of 
the aperture, where they turn abruptly outward and continue at nearly right 
angles to the axis. Most of the specimens consist simply of an aggregation 
of cell tubes, but some of them have apparently an intercellular substance. 
This species may be distinguished from C. fasciculata by its smaller size. 
Formation and locality. Upper Helderberg group, Falls of the Ohio river. 
Clonopora incurva. 
PLATE LXVI, FIGS. 5, 6. 
Clonopora incurva, Hall. Trans. Albany Institute, vol. x, abstract, p. 20. 1881. 
Zoarium about 1.50 mm. in diameter. Length of cell tubes from 3.50 to 4 mm., 
gradually enlarging to the aperture, where the diameter is about .50 mm. 
Eight or ten cells commence growth at the same time at the center of the 
stipe, gradually diverging till within 1.50 mm. from the apertures, when 
they turn abruptly outward. The apertures are spirally arranged, the group 
of cells being umbelliform, the zoarium consisting of a succession of these 
groups of cells. 
Formation and locality. Upper Helderberg group, Manlius, N. Y. 
