THE CTOLOPHORID LAND MOI/LTJSKS OF AMERICA 223 



Upper surface not malleated — Continued. 



Posterior angle of aperture not auriculate — Continued. 

 Shell not decidedly depressed — Conl inued. 

 Aperture large — Continued. 



Ajxial ribs of umbilical wall not stronger than 

 those on upper surface — Continued. 



Last whorl not regularly finely ribbed. 



Umbilicus very broad peruvianum 



Umbilicus not very broad. 



Summit of last whorl appressed to 



preceding turn salengoense 



Summit of last whorl not appressed 

 to preceding turn. 



Shell helicoid masvense 



Shell depressed-helicoid. 



Suture impressed — , agassizi 



Suture not impressed nevadense 



Aperture not large. 



Last whorl deflected below subperipheral brown 

 band. 



Umbilicus narrow fasciatum 



Umbilicus moderately broad pazi 



Last whorl not deflected below subperipheral 

 brown band. 

 Base with a median brown band. 



Peristome with a sinus below basal brown 



band caucaense 



Peristome without a sinus below basal 

 brown band. 

 Greater diameter more than 27 mm_ colombiense 

 Greater diameter less than 25 mm. 



Upper surface regularly flnely ribbed- perezi 

 Upper surface not regularly finely 

 ribbed. 



Suture strongly impressed boliviense 



Suture not strongly impressed- redfieldi 

 Base without median brown band. 



Greater diameter more than 27 mm currant 



Greater diameter less than 25 mm. 



Aperture deflected below subperiph- 

 eral brown band nanum 



Supraperipheral light zone very 



conspicuous merrilli 



Supraperipheral light zone obso- 

 lete pulchellum 



Aperture not deflected below subpe- 

 ripheral brown band. 



Upper surface with oblique 



scratches popayanum, 



Upper surface without oblique 

 scratches. 



Dark band covering half of 



base balsasense 



Dark band not covering half 

 of base cardozi 



