CORALS AND BRYOZOA. 157 



Formation and locality. Upper Helderberg group. Corniferous limestone, Cen- 

 tral New York. 



Fenestella (Polypora) propeia. 



PLATE XXXIV, FIGS. 10-13. 



Fenettella propria. Hall. Trans. Albany Institute, vol. x, abstract, p. 22. 1881. 



" " " Report of State Geologist for 1882. Expl. pi. 27, figs. 10-13. 1883. 



Bryozoum infundibuliform, 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 

 ram., 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. 



Fenextdla aevieata. Hall. Trans. Albany Institute, vol. x, abstract, p. 21. 1881. 



•' {Polypora.) aculeata. Hall Report of State Geologist for 18S2. Expl. pi. 28, figs. ."J-V. 1883. 

 " " " " Report of State Geologist for 1885, advance sheets. Expl. pi. 40, 



figs. 6-11. 1886. 



Bryozoum infundibuliform, arising from a broadly spreading striated base; 

 pedicel short, thick. Branches moderately strong, width above a bifurcation 



