40 
PALEONTOLOGY OF NEW YORK. 
Ptilodictya nebulosa. 
PLATE XVII, FIGS. 13-18. 
Escharopora nebulosa, Hall. Twenty-sixth Rept. N. Y. State Mus. Nat. Hist., p. 99. 1874. 
“ “ “ Thirty-second Rept. N. Y. State Mus. Nat. Hist., p. 162. 1879. 
In part Escharopora ( Ptilodictya) tenuis, Hall. Report of State Geologist for 1882. Expl. pi. 17, figs. 
7-13. 1SS3. 
Escharopora (Ptilodiciya) nebulosa, Hall. Report of State Geologist for 18S2. Expl. pi. 17, figs. 14-16. 1883. 
Paleschara bifoliata, Hall. Twenty-sixth Rept. N. Y. State Mus. Nat. Hist., p. 107. 1874. 
Escharopora (f Paleschara) bifoliata. Hall. 'Thirty-second Rept. N. Y. State Mus. Nat. Hist., p. 162. lS7y. 
Paleschara? foliata (in error), Hall. Report of State Geologist for 1882. Expl. pi. 17, figs. 17, 18. 1883. 
Zoarium a thin foliate expansion, with a thickened, narrow, striated base, 
from which it abruptly expands. Cells tubular, arising obliquely from a 
mesotheca; arranged in subparallel longitudinal rows, rarely interrupted by 
the intercalation of additional rows. Apertures oval or subquadrangular, a 
little longer than wide; length 30 mm. Cell walls coalescing and thickened 
on the surface by silicilication, forming prominent longitudinal ridges. Sur¬ 
face marked by slightly elevated monticules, the centres of which are distant 
from each other about 3 mm.; on these the cells are larger than the others 
and the cell walls thicker; width of the largest specimen observed 70 mm. 
This species is readily distinguished from the others by its broadly spreading 
form and the numerous slightly elevated monticules. 
The fossil described as Paleschara bifoliata in the Twenty-sixth Report of the 
State Museum of Natural History has proved, on further examination, to be a 
specimen of Ptilodictya nebulosa , in a crushed and distorted condition. 
Formation and localities. Lower Helderberg group, Catskill creek, and near 
Clarksville, N. Y. 
RHINODICTYA, Ulrich. 1882. 
RhINODICTYA ? GRANULOSA, 11. Sp. 
PLATE XVII, FIGS. 5, 6 ; AND PLATE XXIII A, FIGS. 18, 19. 
In part Escharopora ( Ptilodictya ) lirata, Hall. Report of State Geologist for 1882. Expl. pi. 17, figs. 
1-6. 1883. 
Zoarium consisting of a bifurcating flattened stipe; bifurcations very infrequent. 
Base obtusely pointed ; sides essentially parallel, width 1.50 mm.; transverse 
