SWALLOW AND HAWN—THE ROCKS OF KANSAS. 197 
the anterior and the other on the Seine are side; those on the 
dorso-lateral angles have one nodule on every iternate cham- 
ber; the nodules around the umbilicus are smaller and less 
numerous. Septa very concave, periphery curved back on the 
dorsal and lateral margins, forming a rounded sinus in the 
dorsal channel, and a more obtuse curve on the flat lateral sur- 
faces; siphuncle large, sub-central ; wmbilicus large; aperture 
small, sub-ovate. 
specimens are imperfect casts of the last volution, from 
which we can not determine the surface markings or the num- 
ber of volutions; but it may be easily identified te the ar- 
ent of the nodules and septa. 
aj. Hawn’s sven from the valley of the Cotton-wood, 
where it was associated with Monotis Halli and Pecten 
Cleavelandicus 
OrTHocrRas KickaProornsg, Swallow. 
longate, conical, taperin dually, sub-cylindrical, 
lightly flattened on the side meh the Y aplaneles septa 
convex, distant less than one-third their smallest diameter ; 
periphery grin iocars and slightly eurved in the direction of 
the major axis; siphuncle small, eccentric, one-third of the 
- diameter from the Reena side. Surface markings not seen. 
: 2h collection from the Upper Permian Rocks, 
near Hill Fork. | 
— 
; ge 
