100 
PALAEONTOLOGY OF NEW YORK. 
SCALARIPORA, Hall. 1881. 
SCALARIPORA SCALARIFORMIS. 
PLATE XXIX, FIGS. 4-8. 
Scalaripora scalar iformis, Hall. Trans. Albany Institute, vol. x, abstract, p. IS. 1881. 
“ “ “ Report of State Geologist for 1S85, advance sheets. Expl. pi. 29, figs. 
4-S. 1886. 
Zoarium composed of an irregular group of triangular prismatic branches ; faces 
of the branch equal, width from 3.50 to 4 mm., very concave, the concavity 
along the middle sub-angular; traversed transversely, at intervals of about 
1.50 mm., by very thin, celluliferous scalm, having a height at the middle of 
the branch of about 1 mm., thickness .20 mm. Cells tubular, arising from 
the radiating inesotheca and from the mesotheca of the scalrn, the latter being 
very oblique, and nearly parallel with the surface. Cell apertures circular, 
sometimes papillose, diameter about .24 mm.; irregularly disposed, frequently 
in contact: peristomes strong, sometimes equally elevated, at other times 
the posterior margin is the most elevated. Intercellular space irregularly 
vesiculose. 
This species differs from S. subconcava in its larger branches, the deeper con¬ 
cavity of the sides, and the comparatively more frequent bifurcations. 
Formation and locality. Upper Helderberg group, Falls of the Ohio river. 
SCALARIPORA SUBCONCAVA. 
PLATE XXIX, FIGS. 1-3. 
Scalaripora subconcava, Hall. Trans. Albany Institute, vol. x, abstract, p. 18. 1881. 
“ “ “ Report of State Geologist for 1SS5, advance sheets. Expl. pi. 29, figs. 1-3. 
18S6. 
Zoarium composed of triangular branches; sides equal or sub-equal, width from 
1 50 to 2 mm., slightly concave; scalae occurring at intervals of about 1.30 
mm., height .50 mm., thickness .25 mm. Cell apertures nearly circular, 
diameter about .18 mm; irregularly disposed. Peristomes thin, equally or 
unequally elevated. Intercellular space vesiculose. 
