58 PALEONTOLOGY OF NEW YORK. 



EUOMPHALUS (StRAPAROLLUS) INOPS. 



1'I.VH. XVI, Klli. s. 

 Euomphalus inops, Hall. Illustrations "of Devonian Fossils : Gasteropoda, pi. 16. 1876. 



Shell discoid; spire depressed-convex, the apex slightly elevated above the 

 plane of the outer volution; lower side broadly and deeply concave. 

 Volutions three or more, curving gently inwards from the periphery, 

 without angularity at the dorso-basal margin. Upper side of volutions con- 

 vex, the last one rounded ; a transverse section near the aperture distinctly 

 broad oval, with the lower side making a longer curve than the upper. 



Surface concentrically striated. 



This species is known at present in a single specimen which diners suffi- 

 ciently from all the others in the New York rocks to be readily distinguished 

 by the peculiar concavity of the umbilical area. In general aspect this form 

 resembles the young of E. Decewi, but the volutions increase in size less 

 rapidly, the umbilical depression is comparatively deeper, and there is no 

 evidence of angularity of the outer volution. Compared with E. Hecale of the 

 Chemung group, the lower side of the volution is more abruptly curving into 

 the umbilicus, and not flattened as in that species (fig. 10, plate 16). 



Formation and locality. In the Schoharie grit, at Schoharie, N. Y. 



EUOMPHALUS (StRAPAROLLUS) RUDIS. 



PLATE XVI, FIGS. 6, 7, 



Euomphaliui rudig, Hall. Illustrations of Devonian Fossils: Gasteropoda, pi. 16, figs. 6,7. 1876. 



Shell discoid. Volutions about four when entire, rounded above and slightly 

 less convex below, curving abruptly from the inner side into the broad 

 umbilicus ; periphery rounded ; section near the aperture broadly oval ; 

 inner volutions rising above the plane of the outer one. 



Surface marked by fine striae of growth, which are often irregular and crowded 

 in fascicles, and sometimes become sharply defined towards the aperture. 



The specimens of this species are imperfect, and the entire characters cannot 



