Report of the State Geologist 81 



Stictopora interstriata. 



Stictopora interstriata, Hall. Trans. Albany Institute, vol. x, p. 191, 1881. 



Report of State Geologist for 1883, p. 45, 1884. 

 " " ** Palaeontology of New York, vol. vi, p. 259, pi. 



Ixii, figs. 7-12, 1887. 



This species will be easily distinguished from S. incisuraia by 

 the narrow, somewhat rigid form, with essentially parallel mar- 

 gins, and the numerous interapertural striations ; from >S'. grani- 

 fera it may be distinguished by its narrower, more rigid form, and 

 the essentially parallel margins, >S^. granifera being much expanded 

 before bifurcation ; also, by the somewhat more regularly dis- 

 posed cell apertures, the spinuliform processes from the inner 

 face of the cell walls, the more slender and much more 

 numerous interapertural striations, and the absence of nodes or 

 granules on the striations and peristomes. When that species is 

 worn,- so that the granules are obsolete, the similarity of the two 

 species is much greater. From Intrapora puteolata of the Upper 

 Helderberg group it is distinguished by the more rigid appear- 

 ance of the frond, the essentially parallel margins, the larger, 

 more distant cell apertures, and the spinuliform processes from 

 the inner face of the cell walls. 



Formation and locality. — Hamilton group. Fall-brook, four miles 

 from Canandaigua lake, Ontario county, N. Y. 



Stictopora recubans. 



stictopora recubans, Hall. Palaeontology of New York, vol. vi, p. 260, pl. 



Ixiii, figs. 20, 21, 1887. 



The characteristics of the species are the comparatively broad, 

 flat, non-celluliferous marginal space, and the oblique, recumbent 

 marginal apertures, with a great portion of their cell walls exposed 

 above the substance of the frond. This species very closely 

 resembles S, vermicula of the Upper Helderberg group, but the 

 non-celluliferous marginal space is wider, the ranges of apertures 

 are fewer in number, there being eleven or twelve ranges on that 

 species, the ranges of apertures are more distant, the apertures are 

 not so distinctly pustuliform, the cell walls of the marginal aper- 

 tures are more exposed, and t£e longitudinal ridges are more 



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