32 
PALAEONTOLOGY OF NEW YORK . 
Lichenalia serialis, n. sp. 
PLATE XIII, FIGS. 17, IS ; AND PLATE XV, FIG. 6. 
In part Lichenalia torta, Hall. Thirty-second Rept. N. Y. State Mus Nat. Hist., p. 157. 1880. 
Lichenalia tort a {tortuosa in error). Report of State Geologist for 1882. Expl. pi. 13, tigs. 17, 18; pi. 15, 
fig. 6. 1883. 
Zoarium explanate, thin. Cells tubular, very oblique, alternating and imbri¬ 
cating. Apertures circular, diameter .40 mm.; generally regularly disposed: 
margins strong, the posterior portion elevated slightly more than the anterior. 
Interapertural space marked by short interrupted striations. Maculae desti¬ 
tute of cell apertures, distant from each other 6 mm.; apertures adjacent to 
them larger than on other portions of the frond. 
This species may be distinguished by the large, circular cell apertures, and 
their regular arrangement. 
Formation and locality. Lower Helderberg group, near Clarksville, Albany 
county, N. Y. 
Lichenalia distans. 
PLATE XV, FIGS. 8, 9. 
Lichenalia distans , Hall. Thirty-second Rept. N. Y. State Mus. Nat. Hist., p. 157. 1879. 
“ “ “ Report of State Geologist for 1882. Expl. pi. 15, figs. 8, 9. 1883. 
Zoarium consisting of lamellate expansions, free or encrusting. Thickness 
1 mm. Cells tubular; apertures somewhat variable, usually oval or nearly 
circular, sometimes sub-quadrangular, and occasionally sub-triangular, length 
from .35 to .44 mm., width generally a little less than the length; irregu¬ 
larly and very closely disposed: margins thin, not prominent, except at 
the posterior end, where they are strongly and abruptly elevated. Mesopores 
variable in size, from one to two ranges between adjacent apertures : margins 
thin and slightly raised, rendering the mesopores obscure. Intercellular 
space vesicular ; vesicles comparatively large. 
Over the greater portion of the specimen the margins of the apertures are 
of equal height, but this is probably due to weathering; on some portions of 
the zoarium they are so sharply elevated that in an oblique view they have 
the appearance of spines. 
Formation and locality. Lower Helderberg group, Schoharie, N. Y. 
