22 The Paleontologist. [Jan. 15, 



tributed over the surface, a line or more apart, are small irregularly shaped maculae bear- 

 ing no cells or pores of any kind that have been observed. The structure of the cells 

 cannot be made out from the many examples so far examined, owing, perhaps, to the 

 manner of the lime crystalization. 



This fossil must have attained quite large dimensions, growing, apparently in an erect 

 position. Dr. Welch informs me that he has fragments, broken from a mass of a single 

 polyzoary as large as a salt barrel. It divides readily at the central laminar axts, the outer 

 surfaces adhering mostly to the rock which seems to have formed in and around it ; this 

 adherence to the rock and slight cohesion at the central laminar axis, explains the common 

 occurrence of the exposure of the latter and the rarity of the outer surfaces showing calices. 



This seems to be quite an abundant fossil in the rocks of the Clinton Group — Upper 

 Silurian, near Wilmington, Clinton Co., O. 



GENUS SAGENELLA, (Hall.) 



Sageoella striata, (sp. nov.) (James.) [striata — minutely fluted.) 



Polyzoary consisting of thin expansions of various forms, irregular in outline. Grown 

 upon foreign substances — mostly corals — from ^ a line to one line or more in thickness 

 in the middle, and thinning out to almost nothing at the borders. Surface ornamented 

 by very fine sinuous striae, which radiate from a central or sub-central elevation to the 

 very thin irregular margins. In some cases the cells between the striae can hardly be 

 made out, in others, ho^vever, they are distinct — long in proportion to width — resembling 

 the description and figure of S. inembtanacea, sp. Hall. (Pal. N. Y., Vol. 2, pp. 172. 



At the subcentral prominences, from which the striae radiate, there are generally circu- 

 lar depressions, one line, more or less, in diameter, with a small pit, sometimes, in the 

 center, at which point the surface striae commence. This circular depression has some- 

 what the appearance of the base attachment of a column, but nothing like a column has 

 been noticed in my case, that I am aware of, and the fact of the surface striae extending 

 uniformly to the central point is opposed to such a view. 



The size of different specimens vary from ^ to ^ of an inch in diameter, conforming 

 to the surfaces of the objects to which they are attached — flat, undulating or cylindrical. 



The examples collected by the writer were all found at the horizon of the hill tops at 

 Cincinnati. Cincinnati Group. 



GENUS DICTYONEMA, (Hall.) 



Dictyonema irregularis. (Hall.) Canadian Organic Remains. Decade II, 1855. 



The writer has in his cabinet a good specimen resembling very closely the above named 

 species, as defined and figured by Prof. Hall, but much larger in outline — more expanded 

 — found Sept. 1877 in place, in a bed of blue shale, near Symmes station, (M. & C. R. R.) 

 Hamilton Co., Ohio, Cincinnati Group. The variations seem so slight as to not justify a 

 new species. Prof. Hall's type specimens were found in the Quebec Group, Lower 

 Silurian, Canada. 



Another small specimen of the same Genus, found in the bed of Obanon Cr., Clermont 

 Co., O., differs materially but there is not enough of it for satisfactory description. 



GENUS CRANIA, (Eetzius.) 



Crania COStata. (sp. nov.) (James.) (fostata — ribbed.) 



Shell el'iptical and regular in outline, prominently convex. Apex of the dorsal valve 

 situated about y^ the distance from the cardinal border, and nearly central measuring 

 transversely. The shorter slopes more abrupt than the longer. Surface marked by rather 

 coarse, simple, sinuous costae. Ventral valve not observed. Size of the example from 

 which this description is made ^x^ of an inch. Attached to a fragment of shale. 



This species differs from C. laelia, Hall, in the very much coarser costae, which seem to 

 cross the shell in one direction, (not radiating from the apex), in the outline of the shell, 

 in the less eccentric apex, and much larger size. Altogether different in general ap- 

 pearance. 



Position and locality — Lower Silurian, Cincinnati Group. Found by Dr. L. B. Welch 

 of Wilmington, Clinton Co., O., near that place. The type specimen is in the finder's 

 cabinet. 



Crania asperula (sp. nov ) (James.) (aspemla — roughish.) 



Shell subcircular in outline, moderately convex. Apex of dorsal valve close to the 

 cardinal margin. Surface marked by rather coarse, rough, slightly curved striae. The 

 roughish surface is caused partly by irregular, closely set transverse lines crossing the 

 longitudinal striae, and ]5artly by variations of the latter. The striae are drawn closely 

 together at the cardinal margin, giving it a somewhat crenulated appearance. Ventral 

 valve unknown. 



