CORALS AND BRYOZOA. 
157 
Formation and locality. Upper Helderberg group. Corniferous limestone, Cen¬ 
tral New York. 
Fenestella (Polypora) propria. 
PLATE XXXIV, FIGS. 10-13. 
Fenestella ■propria, Hall. Trans. Albany Institute, vol. x, abstract, p. 22. 1SS1. 
“ “ “ Report of State Geologist for 1882. Expl. pi. 27, figs. 10-13. 1883. 
Bryozoum infunclibuliform, of lax growth, fronds large. Branches moderately 
strong, sinuous, angular, carinated, width above a bifurcation .50 mm., in¬ 
creasing to .90 mm.; bifurcations at intervals of from 8 to 30 mm., seldom 
less than 12 mm. Interstices wider than the branches. Dissepiments 
slender, angular, carinated, width .33 mm., four or five in the space of 5 
mm., slightly depressed below the plane of the branches and much expanded 
at their junction. Fenestrules sub-quadrangular or oval, length from 1.75 
to slightly more than 2 mm., width about one-half the length. 
On the celluliferous face the branches are rounded. Dissepiments angular, 
carinated, depressed. Fenestrules of the same appearance as on the opposite 
face. Cell apertures usually in three and four ranges, sixteen in the space 
of 5 mm., separated by slightly more than the diameter of an aperture, 
situated on low, rounded ridges. 
This species may be distinguished by the lax appearance of the frond, the 
frequently sinuous, angular, strongly carinated branches on the non-celluliferous 
face, and the low rounded ridges of the celluliferous face of the branches, in 
which respects it differs from any other species of this formation. 
Formation and locality. Upper Helderberg group, near Buffalo, N. Y. 
Fenestella (Polypora) aculeata. 
PLATE XXXV, FIGS. 5-7 ; AND PLATE XL, FIGS. 6-11. 
Fenestella aculeata, Hall. Trans. Albany Institute, vol. x, abstract, p. 21. 1881. 
“ ( Polypora ,) aculeata, Hall Report of State Geologist for 1882. Expl. pi. 28, figs. 5-7. 1883. 
“ “ “ “ Report of State Geologist for 1SS5, advance sheets. Expl. pi. 40, 
figs. 6-11. 1SS6. 
Bryozoum infundibuliform, arising from a broadly spreading striated base; 
pedicel short, thick. Branches moderately strong, width above a bifurcation 
