110 PALEONTOLOGY OF NEW YORK. 



Fenestella serrata. 



PLATE XUVU, FIGS. H-l». 

 F)eiu*UUa samUa, HkLh. Trans. Albany Institute, vol. x, abstract, p. 28. 1881. 



Brvozoum iiifiindibuUform, frond compact. Branches slender, width above a 

 bifurcation from .20 to .25 mm., increasing to .40 or .42 mm., very gradually 

 enlarging, rounded or sub-angular, sometimes smooth but usually nodose, the 

 nodes on some of the fronds being very prominent, sometimes granulose ; 

 bifurcations distant. Interstices usually of about the same width as the 

 branches, but .sometimes one and one-half times and occasionally twice the 

 width. Dissepiments slender, width from .20 to .25 mm., rounded, slightly 

 depressed, eight or nine in the space of 5 mm. Fenestrules oval, length 

 usually from .35 to .40 mm., width .25 mm. 



On the celluliferous face the branches are angular. Dissepiments acutely 

 angular, carinated, depressed below the plane of the branches. Fenestrules 

 of the same appearance as on the opposite face. Cell apertures in two ranges, 

 opening laterally, twenty-two in the space of 5 mm., separated by 

 slightly less than the diameter of an aperture : margins thin, slightly ele- 

 vated. Surface carinated ; carinse strong, elevated, with sharp, triangular, 

 prominent nodes, about equal in number to the cell apertures. 



The non-celluliferous face resembles very nearly some varieties of F. stellata. 

 The celluliferous face may be distinguished by the sharply angular branches 

 and dissepiments, which give to this face of the frond the appearance of being 

 divided into small squares, a feature distinguishing it from any otlier species. 



Formation and locality. Upper Helderberg group. Falls of the Ohio river. 



Fenestella verrucosa, n. sp. 



PLATE XLU, FIG. 11 ; I'LATK XLVI, FIGS 22, 24. 



Bryozoum infundibuliform, fronds large, compact. Branches slender, width 

 above a bifurcation .20 to .25 mm., increasing to .40 and .45 mm., with 

 numerous small nodes, closely and irregularly disposed. Usually, when the 



