46 PALEONTOLOGY OF NEW YORK. 



creasing in size to a bifurcation ; marked by from one to four sharp lines or 

 striae, which are strongly nodose along their summits. Bifurcations infre- 

 quent. Dissepiments slender, depressed. Interstices usually equal to the 

 width of the branches. Fenestrules oval or sub-quadrangular, length about 

 twice the width. 



On the fragment described there are from nine to eleven branches in the 

 space of 5 mm. measured transversely, and seven fenestrules in the same 

 space measured longitudinally. 



This species bears some resemblance to the non-celluliferous face of some 

 specimens referred io F. (U.) Nervia, but may be readily distinguished by its 

 more slender branches, wider interspaces and sub-quadrangular fenestrules. 



Formation and locality. In the shaly limestone of the Lower Helderberg 

 group, at Schoharie, N. Y. 



FeNESTELLA iEsYLE. 



PLATE XIX, FIGS. 11-13. 



Fmestella SSsyU, Hall. Thirty-second Kept. N. Y. State Mus. Nat. Hist., p. 166. 1879. 

 • " " •' Report of State Geologist for 1882. Expl. pi. 19, figs. 11-13. 1883. 



Bryozoum probably infundibuliform. Branches slender, rounded, marked by 

 obscure striae. Bifurcations frequent, occurring at intervals of from 2 to 

 5 mm. Width of interstices greater than that of the branches. Dissepi- 

 ments rounded, six in the space of 5 mm., slightly expanding at their 

 junction, and on the same plane with the branches. Fenestrules sub-quad- 

 rangular, or broadly oval, width from one-half to two-thirds the length. 



Cell apertures small, circular, opening directly outward, twenty-five in the 

 space of 5 mm. ; disposed in two or three ranges, with sometimes an addi- 

 tional aperture just below a bifurcation. 



Width of branch just above a bifurcation .20 mm., increasing to .50 mm. ; 

 width of dissepiments from .20 to .25 mm. ; fenestrules .60 mm. long. 



The specimen represented by fig, 13, pi. xix, is more lax in its growth than 

 the ordinary forms of this species. 



Formation and locality. Lower Helderberg group, near Clarksville, N. Y. 



