CEPlIALOrODA FROM THE HOKKAIDO. 15 



coil than the posterior, at times a wider one. Umbilicus as wide 

 as the breadth of the whorl. Whorls slowly increasing in diameter 

 with growth, nearly round or somewhat transversely oblong in 

 section and ornamented with numerous ribs (about 50 on a volu- 

 tion). Ribs uniform, smooth, usually simple, rarely bifid; arranged 

 slightl}^ obliquely ; moderately sharp but broad at the l^ase on 

 the external side, thence becoming gradually narrower toward the 

 upper border and suddenly toward the lower border, while they 

 are fine, though still distinct, on the umbilical side. Interspaces 

 between the ribs flat or slightly concave, being twice as broad 

 as the ribs. 



Suture line partly known. External lobe shallow, with a 

 high broad siphonal saddle ; first lateral lobe very broad, regularly 

 bifurcating twice; external saddle symmetrically bipartite, inclining 

 inward ; first lateral saddle broad and also bifid. All the lobes 

 and saddles are finely serrated. 



Of the three examples of this species hitherto found, one (pi. 

 IV., fig. 2.) is a partly septate fragment composed of I2 volutions, 

 measuring 2.5 cm. in diameter at the smaller end. Where the 

 shell is not preserved the ribs appear broad and round, separated 

 by very shallow furrows. The suture line and the siphuncle are 

 also seen in the part above alluded to. The siphuncle is abnormal, 

 being pushed down anteriorly from the normal median position 

 on the external side of the whorl. A quite similar cnse has 

 already been noticed by F. B. Meek on n shell of HeteTOceras 

 tortum Meek and Hayden.^' 



The second specimen (pi. IV., fig. 1.) is a somewhat smaller 

 one, composed also of le volutions. 



1) Meek : Invert. Cret. and Tert. Foss. Upp. Missouri County. Rep. U. S. Geol. Surv. 

 of the Territories. Vol. TX., ISTO. P. 4SI, pi. XXIT., fi^s. 4a, I., c. 



