486 GEOLOGY OF OHIO. 



specimen, which with but little cleaning shows the columellar fold as 

 strongly developed as any of the Ohio specimens. 



Formation and Locality. — In the Coal Measure strata at Carbon Hill, 

 Hocking county, Ohio. Collected and presented by Mr. H. Moores, of 

 Columbus, Ohio. 



Genus LOXONEMA Phillips. 



Loxonema piicatum. 



Plate XI, figs. 14 and 15. 



Loxonema piicatum Whitf., Ann. N. Y. Acad. Sci., 1882, p. 231. 



Shell small and slender, spire elevated, presenting an apical angle of about 

 fifteen degrees ; composed of about eleven volutions, in the example used and 

 illustrated, which are flattened on the surface in the direction of the spire, and 

 marked by strong vertical plicae, which are directed a little forward in their passage 

 across the volution from above downward. The body or largest volution, counting 

 from the lip backward, contains fifteen of these plications, and the volutions above 

 contain nearly the same number; those of the several volutions being in line with 

 those on the one below, but set enough back of it to be in Hue with the slope of 

 the plication. This gives them a somewhat spiral arrangement on the shell, the 

 whole having a twist of about one-fourth of one turn in the length of the shell. 

 On tne last volution the plicae are not distinct much below the bulge of the whorl. 

 Aperture elongate and pointed below. Suture distinct, but not grooved or banded. 

 Columella straight, about half as long as the aperture, solid, and terebra-like ; 

 shell without umbilicus. 



The species belongs to a group of the genus which has but few 

 representatives in our Coal Measures ; and even those that are nearest 

 allied to it appear to differ in the form of the columella, which is some- 

 what peculiar ; and if other species should appear presenting these same 

 characters, it may be necessary to separate them generically from the 

 true Loxonema. 



Formation and Locality.— -In the Coal Measures of Carbon Hil^ 

 Hocking county, Ohio. Collected by H. Moores, Esq. 



CEPHALOPODA. 



Genus NAUTILUS Breyn. 



Nautilus Ortoni. 



Plate XII, fig. 20. 



NautilUs Ortoni Whitf, Ann. N. Y. Acad. Sci., 1882, p. 231. 



Shell of medium size, and consisting of about two and a half or three closely 

 coiled volutions, but which are not at all embracing ; the outer one being simply 

 in close contact with the medio-dorsal portion of the next within, and exposing 

 nearly the entire dorso-ventral diameter of the shell. Volutions trausver^ely sub- 

 pentangular, being angularly convex on the back, strongly subangular on the sid; s 

 and concave on the abrupt umbilical slope, which forms a somewhat sigmoidal 

 curve resembling an^ogee moulding, while the slightly concave ventral surface is 

 quite narrow, and forms a fifth surface. Lateral angles obtuse or round subangular, 



