142 PALEONTOLOGY OF NEW YORK. 



This species may be distinguished by the elevations around the fenestrules, 

 the distant scalse which are directed obliquely away from the base, and not 

 curved; and by the circular interstices. 



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



/. Forms similar to Unitrypa but having the scala. distant from each other. 

 Fenestella (Unitrypa ?) consimilis, n. sp. 



PLATE LIV, FIGS. 7-9. 



Bryozocm consisting of large infundibuliform fronds, very gradually expanding 

 from the base. The non-celluliferous face has not been observed. 



On the celluliferous face the branches are moderately slender, width .35 

 mm., increasing to .60 mm., very gradually enlarging, essentially parallel, 

 straight, angular. Interstices of the same width as the branches. Dissepi- 

 ments strong, width .60 ram., rounded, slightly carinated, much depressed, 

 four in the space of 6 mm. Fenestrules oval, length .90 mm., width .35 mm. 

 Cell apertures in two ranges, opening directly outward, very broadly oval, 

 slightly oblique to the axis of the branch, sixteen in the space of 5 mm., 

 separated by half the diameter of an aperture : margins elevated, indenting 

 the borders of the fenestrules. Branches carinated ; carina .60 mm. high, 

 at first very thin, but immediately expanding, the summit having pre- 

 cisely the appearance of the branches of a non-celluliferous face ; width above 

 a bifurcation .33 mm., increasing to about .60 mm., rounded, slightly cari- 

 nated. ScalaB or pseudo-dissepiments slender, width about .30 mm., rounded, 

 slightly carinated, on a plane with, or elevated above the carina, five in the 

 space of 5 mm. Fenestrules oval, length .70 mm., width .35 mm. 



This species is very easily distinguished from any other at present known 

 in this geological formation. 



Formation and locality. Upper Helderberg group, Walpole, Ontario, Canada. 



