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SCALARlADiE. 



The wentle-trap, once famous for the enormous value set 

 upon it by collectors, and always remarkable for its beauty, 

 constitutes with its allies a small group, of which the genus 

 Scalaria is the type. In this family a spiral shell with 

 an entire aperture is combined with an animal whose head 

 is not produced into a muzzle, but furnished with a re- 

 tractile trunk. The sexes are distinctly separated. The 

 eyes are immersed at the external bases of subulate ten- 

 tacula. The dentition of the lingual riband is very pe- 

 culiar ; there is no central denticle, but transverse rows 

 of teeth formed of unguicular, simple uncini. The animals 

 of this family are probably predacious. 



SCALARIA, Lamakck. 



Shell spiral, pyramidal or turreted, firm, often strong 

 in texture, ornamented with ribs, ridges, or varices, which 

 cross the whorls in the direction of the length of the 

 shell, smooth, or spirally striated between them. Mouth 

 rounded, often subangulated below, lip thickened and 

 entire. Operculum corneous, paucispiral. 



Animal having an angularly lunated head, with two 

 approximated long pointed tentacula; eyes immersed at 

 their external bases ; mouth inferior, with a retractile 

 trunk ; mantle a rudimentary siphonal fold, simple-edged ; 



