CORALS AND BRYOZOA. 
109 
approaching in character the sub-genus Ptiloporella and also by the large cell 
apertures in contact, opening directly outward. 
Formation and locality. Upper Helderberg group, Falls of the Ohio river. 
Fenestella stellata. 
PLATE XLV, FIGS. 14, 15 ; AND PLATE XLVII, FIGS. 20-36. 
Fenestella stellata, Hall. Trans. Albany Institute, vol. x, abstract, p. 29. 1881. 
“ “ “ Report of State Geologist for 1885, advance sheets. Expl-. pi. 45, figs. 14, 15. 
1886. 
“ sculptilis, Ulrich. Journal of the Cincinnati Acad. Sciences. Cont. Am. Pal., p. 10, pi. 1, fig. 3. 
1886. 
Bryozoum infundibuliform. Branches moderately slender, width above a bifur¬ 
cation .25 mm., increasing to .50 mm., rounded or sub-angular, sometimes 
smooth, at other times with frequent, prominent, irregularly disposed nodes. 
Interstices usually narrower than the branches. Dissepiments compara¬ 
tively strong, width .25 mm., sometimes oblique, rounded or angular, on a 
plane with the branches, six in the space of 5 mm. Fenestrules oval, 
length from .50 to .55 mm., width from .25 to .30 mm. 
On the celluliferous face the branches are sometimes angular and cari- 
nated, but usually both the branches and dissepiments are traversed by 
narrow grooves or channels, with sharp margins, which are sinuous on 
the branches. Fenestrules narrower than on the opposite face. Cell 
apertures in two ranges, opening somewhat laterally, twenty-four in the 
space of 5 mm., separated by less than half the diameter of an aperture: 
margins elevated, indenting the borders of the fenestrules. Along the middle 
of the branches there is a row of very prominent nodes, which are some¬ 
times conical, at other times they are expanded at the summit and present 
a stellate appearance. Carinated and channeled branches occur on the same 
frond. 
The peculiar channeling of the branches and dissepiments, and the promi¬ 
nent, frequently stellate nodes serve to distinguish this species from any other. 
Formation and locality. Upper Helderberg group, Falls of the Ohio river. 
