78 
PALAEONTOLOGY OF NEW YORK. 
tions though very narrow frequently preserve the crescentic appearance com¬ 
mon to the denticulations of many other species. The gradation through 
various species from this form of denticulation to the wide crescentic form is 
very gradual. Many specimens have been examined, but I have been unable 
to discover the accessory cells mentioned by Mr. Ulrich as constituting a dis¬ 
tinctive character. 
Formation and localtiy. Upper Helderberg group, Falls of the Ohio river. 
Lichenalia lunata, var. tubulata. 
PLATE XXXI, FIGS. 28, 29. 
Lichenalia lunata, var. tubulata , Hall. Report of State Geologist for 18S5. Expl. pi. 31, figs. 28, 29 1887. 
This associated variety differs from ordinary forms of L. lunata , in its tubular 
mode of growth. 
Lichenalia substellata. 
PLATE XXVI, FIG. 26; AND PLATE XXX, FIGS. 1-11. 
Lichenalia substellata, Hall. Trans. Albany Institute, vol. x, abstract, p. 7. 1881. 
“ “ “ Report of State Geologist for 1882. Expl. pi. 24, fig. 26. 1883. 
“ Report of State Geologist for 1885, advance sheets. Expl. pi. 30, figs, l-l 1. 
1886. 
? F'istulvpora normalis, Ulrich. Cont. Am. Pal., vol. i, No. 1, p. 20. 1886. 
Zoarium consisting of lamellate expansions, or of masses formed by the super- 
imposition of successive layers of irregular growth, frequently contorted. 
Cells cylindrical, usually at right angles to the surface ; septa infrequent 
or wanting. Cell apertures circular, diameter .33 mm.; closely and 
irregularly disposed: peristomes strong, generally the posterior portion is 
the more distinctly elevated, oblique, and occasionally denticulated. Sur¬ 
face marked by flat or slightly elevated substellate non-celluliferous maculas, 
the centers of which are distant from each other about 4 mm. The 
apertures immediately adjacent to these are radiatingly disposed, larger and 
more oblique than on other portions of the frond. Intercellular space, near 
the base, occupied by irregular vesicles, above by septate tubuli; from five to 
eight septa in the space of 1 mm. Occasionally the apertures are operculate, 
