278 HELIC1NA. 



elude many incongruous shells, and exclude others which notwith- 

 standing are enumerated in the lists hitherto published. 



I have endeavoured to group together, without defining, those 

 species most nearly resembling eaeh other, and if the groups so 

 formed do not correspond with the generic divisions referred to 

 above, it is because particular characters are not always found in, 

 or confined to, shells of the same general aspect. Generic 

 names require generic definitions, and the genera into which the 

 Helicinee have been divided cannot be defined. Yet a system of 

 general grouping without such definitions may be usefully em- 

 ployed. 



This being a second monograph, I have not here given full 

 descriptions of the species, but have been content with mention- 

 ing in a word or two about each some peculiarity of the shell as 

 compared with others of the same group, — trusting in this way, 

 by the help of the figures, to give a better idea of the species 

 than would be done by more elaborate descriptions in which 

 many characters would have to be repeated. 



Helicina. 



Sect. I. Apertu.rd inter columellam ei labrum emarginatd. 



With a notch or depression in the outer lip next the columella. 

 Including genus Alcadia. 



a. Testa solida, labro crasso. — Solid, thick-lipped. 



1. Briar^ea, Poey, (f. 1, 2, 3.) — Laevigata, depressa. — 

 Smooth, depressed. 



2. Titanica, Poey, (f. 4.) — Rugata, magis elevata. — 

 Wrinkled, more elevated. 



3. Sagiiaiana, Orb., (f. 5,447.) — Laevigata, elevata. — Smooth, 

 elevated. 



4. Bastitiana, Poey, (f. 6.) — Labro oblicpie producto. 



5. Bayamensis, Poey, (f. 7.) — Subrotunda, distanter rugata. 

 ■ — Rather round, distantly wrinkled. 



6. Cataliniana, Pfr., (f. S.) — Quam sp. 3 magis elevata. — 

 More elevated than sp. 3. 



7. pulcherrima, Lea, (f. 9. 10.) — Rotunda, crebre lirata. — 

 Round, closely ridged. 



8. submarginata, Gray, (f. 11, 12, 13.) — Spiraliter lineo- 

 puncturata. — Spirally punctured in lines. 



