110 
BELLEROPHON costatus, 
TAB. CCCCL XX.— Jig. 4. 
Spec. Char. Globose, expanded, subcarinated, 
with slender sharp ribs diverging from the 
undefined band ; axis perforated. 
Syn. Parkinson Org . Item . Vol. p . 3, 141, t. 10, 
f. 6 and 7. 
The carinated form, sharp ribs and undefined but 
broad convex band, distinguish this; the aperture is 
wide and much arched, and the sinus in it deep, leaving 
bent striae upon the band. 
We have but one specimen of this, probably from 
Derbyshire. Parkinson seems to consider it the same as 
Martin’s hiulcus, and it may possibly be his fig. 2, and 
var. a. but he describes the band as flat. 
