171 



PLANAXIS, Lamarck 



(Plates I., II. Thea. PI. 483, 484.^ 



Testa ovato-subpyramidata, solida, plerumque spiraliter 

 sulcata aiit striata ; apertura iiitus crenato-dentata, supra 

 infraque subcanaliculata ; columella prope suturam callosa, 

 infra ad termrnum planata et truncata. 



The aperture terminates in a notch or canal at each end, 

 the callosity at the suture forming one in conjunction with 

 the outer bp, and there being a notch at the lower termina- 

 tion where the columella is flattened and truncated. — The 

 genus Qiioyia is composed of two species [decollatus 11, and 

 Michaudi 12), which have a notch cut out close to the 

 junction of the outer lip behind the callus, which is thereby 

 sharpened into a tooth. 



Species. 



1. SDLCATDS, f. 10, 11, Born. — Magnus solidus late pyra- 

 midatus, sulcis spiralibus crassis rotundis cinctus ; apertura 

 subtrigona, intus valide dentata ; columella lata truncata ; 

 labio externo superne subflexuosim depresso. — Of a greyish 

 colour, mottled and marked variously with brown. 



2. ENCAUSTicus, f. 32, Smith. — P. sulcato similis sed bre- 

 vior, sulcis fere evanidis, maculis quadratis tessellatus, an- 

 fractibus superioribus rotundis, paucis. — The markings have 

 a tessellated character, the grooves are faint and the upper 

 whorls few, round and short. 



3. BREVICDLDS, f. 3. — P. sulccito similis, sulcis fere evanidis, 

 maculis fuscis oblongo-quadratis medio ornata. — Although 

 shorter than sp. 1, it has the same pyramidal form, with 



