CORALS ANl> BRYOZOA. 
37 
The specimen has a general resemblance to a Ptilodictya, but differs in 
having intercellular vesicular tissue. 
Formation and locality. Lower Helderberg group, Clarksville, N. Y. 
STICTOPORA, Hall. 1847. 
Stictopora papillosa. 
PLATE XIII, FIGS. 12, 13; AND PLATE XXIII A, FIG. 16. 
Stictopora papillosa, Hall. Thirty-second Rept. N. Y. State Mas. Nat. Hist., p. 1(51. 1S79. 
“ “ “ Report of State Geologist for 1882. Expl. pi. 13, tigs. 12, 13. 1SS3. 
Zoarium ramose, flattened; bifurcations frequent; width of branch from 2 
to 2.50 mm. Transverse section flattened oval; greatest thickness 1 mm. 
Cell apertures circular, diameter .25 nun., those nearest the margin somewhat 
larger; generally arranged in indistinct longitudinal rows, frequently in con¬ 
tact: margins thick, strongly elevated, oblique, constricting the apertures. 
The papillose margins of the cells, and the elongate form of a transverse 
section of a branch, are distinguishing features of this species. 
Formation and locality. Lower Helderberg group, near Clarksville, N. Y. 
Stictopora obsoleta, n. sp. 
PLATE XXIII A, FIG. 22. 
Zoarium ramose, flattened; bifurcations distant about 10 mm.; width of branch 
2 mm., increasing very slightly in width to the bifurcation. Width of the 
non-celluliferous space at the margin .40 mm. Cell apertures oval, length 
.25 inm., width .17 mm.; disposed in longitudinal parallel rows. 
All the specimens of this species, so far observed, have been worn or macer¬ 
ated, but it is easily distinguished from any other of this formation by its larger 
size and the form and arrangement of the cell apertures. 
Formation and locality. Lower Helderberg group, near Clarksville, N. Y. 
