EULIMID.E. 235 



Ex. M. albula, O. Fabricius, pi. 24, fig. 10. Opercu- 

 lum, M. albula, fig. 10, a. Shell, M. striata, Gray, fig. 

 10, b. 



Moller has described the animal of this genus, which 

 seems to be nearly allied to Turbonilla and AcUs in the 

 short tentacles with the eyes at their inner bases, rudi- 

 mentary tongue, and elongate, narrow foot. The shells 

 are of great beauty and delicacy, and resemble, in many 

 respects, greatly-elongated Actgeons. 



Species of Monoptijgma. 



arncena, A. Adams. pura, A. Adams. 



casta, A. Adams. speciosa, A. Adams. 



coiicinna, A. Adams. spirata, A. Adams. 



fulva, A. Adams. striata, Gray. 



granulata, A. Adams. stylina, A. Adams. 



lauta, A. Adams. suturalis, A. Adams. 



Sub.-gen. menestho, Moller (Pjramis, Couth., not Chem. or 



Schmn.). 



wanting. 



Aperture ovate; columellar lip with the plait obsolete or 

 albula, 0. Fab. striata, Couth. 



Fam. EULIMIDJ:. 



Teeth and lingual membrane rudimentary. Tentacles 

 simple, subulate ; eyes sessile at the outer bases of the 

 tentacles. Mantle enclosed, with a rudimentary siphonal 

 fold. Foot linguiform, produced in front, with a bilobed 

 mentum or fold above the front margin ; operculigerous 

 lobe developed at the sides into even-edged, unequal ex- 

 pansions or lobes. 



