70 
PALAEONTOLOGY OF NEW YORK. 
ally diverging until near the surface, when they abruptly turn outward; 
septa infrequent. Cell apertures oval, length about .22 mm., width from 
one-half to two-thirds the length; closely and irregularly disposed. Inter- 
apertural space spinulose. The branches, when in a perfect condition, are 
covered by closely arranged aculeate processes. Many of the branches are 
annulated, but this feature is not constant. 
In some varieties this species resembles Trematopora ( Trematella ) annulata, but 
may be distinguished by the oval cell apertures. 
Formation and locality. Upper Helderberg group, Falls of the Ohio river. 
Trematopora (Trematella) glomerata. 
PLATE XXV, FIGS. 4, 5. 
Trematella glomerata, Hall. Report of State Geologist for 1885, advance sheets. Expl. pi. 25, figs. 4, 5. 
1886. 
Zoarium ramose, solid; branches from 1.50 to 2 mm. in diameter; bifurcations 
frequent. Cells tubular, in contact for the greater portion of their length, 
slightly diverging as they approach the surface; septa infrequent or want¬ 
ing. Intercellular space apparently solid. Cell apertures usually oval or 
circular, length .30 mm.; closely and irregularly disposed. Interapertural 
area elevated, angular or nodulose. Pseudopores variable in number on 
different portions of the frond, generally infrequent. 
Formation and locality. Upper Helderberg group, Onondaga Valley, N. Y. 
Trematopora (Orthopora) scutulata. 
PLATE XXVI, FIGS. 7, 8. 
Trematopora scutulata, Hall. Trans. Albany Institute, vol. x, abstract, p. 6. 1S81. 
“ “ “ Report of State Geologist for 1882. Expl. pi. 24, figs. 7, 8. 1883. 
Zoarium ramose, solid; branches widely diverging, 1 mm. in diameter; bifur¬ 
cations frequent. Cell apertures oval, length .25 mm., width .18 mm.; dis¬ 
posed in longitudinal parallel rows, alternating, forming oblique transverse 
rows, the latter arrangement being the most conspicuous: peristomes thin, 
inclosing a rhomboidal area, with a minute spinule at each angle. 
