1 he faiiiui of Ihc Maxz'illc Limestone. 



411 



1895. XautHiis {Tciiiiiol-IicHiis) s/^cctabilis. Whitrield, Geol. Surv. Ohio, 

 \"ol. YU. p. 4S0, pi. 1(1, fig. 2-2. 

 Maxvillc limestone: Near Rushville, (Jliio. 



Deseription. — "vShell of medium to large size, compcsed 

 of several volutions, which increase rapidly in size, and are 

 (transversely) elliptical in a transverse section; the diameter 

 from side to side being about one-third greater than the dorso- 

 ventral diameter at the same point ; the lateral edges being 

 obtusely angular, and the dorsal [ventral] portion of the sec- 



Vic. '.^:^. — Rudolobus spcctahilis. Lateral view. (.After Whitliekl.) 



tion larger and more convex than the inner ])art, strongly con- 

 vex and subangular on the back. Inner siu'facc of the volution 

 strongly impressed by the one preceding, which it embraces to 

 near the ])oint of greatest diameter. Uml)ilicus very broad and 

 deep, exposing each of the inner volutions to just beyond the 

 point of greatest transverse diameter, the umbilical siu-face of 

 the volutions being moderately convex but quite al^rupt. The 



