OKISKANY FAUNA OF BECRAFT MOUNTAIN 61 



Isotrypa, sp. indes. 

 Reteporina, sp. indes. 



Fenestella biseriata Hall (?) 



See Paleontology of New York. 6:113, pi. 42, %. 16-18 

 Fronds having the characters of this species are occasionally found 

 The originals of the species were from the Onondaga limestone at 

 Cherry Valley N. Y. 



Hemitrypa columellata Hall 



1887. Fenestella (Hemitrypa) columellata Hall. Paleontology of New York. 

 6:146 



This species, described from the Onondaga limestone of Walpole 

 Ont., is occasionally found in the Becraft mountain Oriskany. 



Hederella magna Hall and Simpson 



Plate 9, flg. 10 



1887. Hederella magna Hall and Simpson, Paleontology of New York. 

 6 : 280, pi. 65, fig. 15 



To this species is referred a Hederella characterized by its 

 short, stout, strongly rugose and somewhat irregular cells, erect at their 

 extremities, growing in a double series which proceed from a central 

 stock generally in part concealed by overgrowth. The cells are larger 

 than in any of the other species here found. 



The original of this species was from the Hamilton shales of 

 York N. Y. 



Hederella arachnoidea, sp. nov. 



Plate 9, fig. 11 



This is the smallest of the species here observed, the zoarium 

 being very fine, creeping in an irregular manner over the surface of 

 attachment, generally showing the biserial stock, but this is often obscured 

 by frequent and irregular branching. The cells are narrow, often flat- 

 tened, branching taking place at quite distant intervals but alternately 

 on opposite sides. The species may be distinguished from H e d . 

 g r a c i 1 i o r by its finer, more elongate cells, its more distant branch- 

 ing and much more diffuse and irregular zoarium. 



