77$ 



NORTH AMERICAN INDEX FOSSILS. 



Differs from H. caloosaensis in having the last whorls free from 

 indications of ribs, well rounded and strongly marked by spirals. 

 Both outer and inner lip strongly lirate on apertural side. 



Cape Fear River Miocenic of North Carolina. 



557. H. (Barbarofusus) exilis (Conrad). Miocenic. 

 Later whorls rounded, owing to prominence of first shoulder 



spiral ; ribs disappear in later whorls ; spirals compound ; aperture 

 less sharply contracted than in preceding. 

 Miocenic or Upper Oligocenic of Florida. 



558. H. caloosaensis (Heilprin). (Fig. ii3i,aandc.) Pliocenic. 

 Shoulder of later whorls flat but angle not pronounced, ribs 



faint on later whorls; spirals mostly primary, more rarely fine 

 secondary ones intercalated; aperture and whorl abruptly con- 

 tracted to the slender canal which is slightly sinuous; inner lip 

 strong, multiplicate ; outer lip strongly lirate. 

 Pliocenic of Florida and the Carolinas. 



559. H. (Barbarofusus) barbarensis (Trask). (Fig. 1132). 



Pliocenic. 

 Spire slender, whorls round, sutures deep, apical angle 30 or 



Fig. 1 132. Heilprinia ^Barbarofusus') 

 barbarensis, X r -5- (After Arnold. ) 



Fig. 1 1 33. Exilia pergracilis. 

 (After Harris.) 



