46 FOSSILS FROM SOUTHERN UNITED STATES— DALE. 



VOL. XVIII. 



UMBONIUM (SOLARIORBIS) UNDULA, new species. 



Sbell small, solid, of three and a half whorls, depressed, dome-like, 

 strougly keeled at the perii^hery, ^vith a round-edged, broad carina, 

 above and below which the whorl is more or less compressed; trans- 

 verse sculpture of about a dozen rounded ripples between the suture 

 and the periphery, the nucleus and the last half of the last whorl being 

 free from them ; these ripples cross the whorl in a flexuous manner, and 

 differ in strength in different specimens; the base also shows radiating 

 flexuous sculpture, but more feeble and obscure; the spiral sculpture 

 consists of the perii)heral carina, and of oblique incised lines, which are 

 absent near the suture and umbilicus, but sharp and distinct periph- 

 erally; they cut the surface at a slight angle with the plane of the 

 periphery; base flatfish, slightly rounded in the middle, the umbilicus 

 moderate, without any well-marked angle or internal sculpture; aper- 

 ture oblique, nearly circular, produced at the upper angle; peristome 

 simple, entire. Diameter, 2.5; height, 1 mm. 



Habitat. — Miocene of the Natural Well, Duplin County, North Caro- 

 lina; Burns, collector. 



Type.— No. 114440, U. S. N. M. 



UMBONIUM (SOLARIORBIS) DUPLINENSE, new species. 



Shell small, solid, of three and a half whorls, rather depressed; sculp 

 ture on the spire of rather even, rounded, oblique, subequal, transverse 

 riblets, with narrower interspaces, crossed by tine, sharp, close-set, spiral 

 stride; an incised line in front of the suture cuts off a narrow^ border, 

 except on the smooth nuclear whorls; the periphery is formed by a 

 strong, blunt-edged keel; the base is rather full, with two more rather 

 strong keels with reticulate sculpture between them, the spirals pre- 

 dominating near the umbilicus and the radials near the periphery; 

 umbilicus small, with an angular border and a single spiral thread 

 within; aperture rounded, oblique, produced on the body whorl, entire. 

 Diameter, 2; height, 0,75 nmi. 



Habitat. — Miocene of the Natural Well, Duplin County, North Caro- 

 lina; Burns, collector. 



Type.— No. 114445, U. S. N. M. 



Though so small, the sculpture is very elegant. 



