Sec. 4. Spirally ribbed or striated ; outer lip diffuse ; columella flat ■ 

 tened or concave. 



H. pulchella, Tankervillii, virginea, globosa, costata. 



Sec. 5. Globose; outer lip confluent with the columella; inner lip 



thin. 



H. zonata, lutea, variegata, neritella, picta, variabilis, Antil- 

 larum, occidentalis. Guadaloupensis, maculata, polita, siuoilis, 

 parva, globulosa, maxima, ambeliana, Zephyrina, pellucida, flavida. 



Sec. 6. Columella as in Sec. 5 ; shell pyramidal. 

 H. Trochulina, conica, elongata, elegans, rupestris, Sloanii. 



Sec. 7. Shell carinated ; outer lip confluent with the columella. 



H. acutissima, Trochiformis, Oxystoma, Carocolla, aggluti- 

 nans r Lazarus, viridis, candeana, carinata, Rotella, pilosa. 



Sec. 8. Shell depressed ; columella angulaled. 



H. Rhodostoma, angulata, fulva, Brasiliensis, sylvatica, oresi- 

 gena. 



Sec. 9. Shell horny ; columella rather angulated, or slightly notched ; 

 outer lip scarcely thickened. 



H. orbiculata, cornea, castanea, nitida, rotunda, minuta, vestita, 

 rugosa. 



DESCRIPTIONS. 



Sec. 1. Lip thickened, sinuous, depressed at the base of the columella. 



Sp. 1. H. aurantia, (pl.i. f. 1, 2.) Gray, Zool. Journ. i. p. 69. 

 Testa globosa, lsevi ; labio externo reflexo, crasso, in medio 

 sub-expanso, postice et antice depresso ; labio interno crasso, ex- 

 panso ; columella lata complanata. 



The peritreme of this globular shell is generally of a light 

 orange colour; it is thick, and the outer lip is depressed above, and 

 at its union with the columella, which is broad and flattened. 



Jamaica. 



2. H. Jamaicensis, (pi. i. f. 3, 4.) nobis. 



T. H. aurantiee simillima, sed magis conica, et magis tenui ; 

 peritremate pallidiore, minus incrassato. 



More conical than the last, with the edge of the aperture thinner. 

 It may be only a variety. 



3. H. h/ema stoma, (pi. i. f. 5, 6. pi. iii. f. 98.) Moricand. 

 Mem. Coq. terr. et. fluv. de Bahia. 



T. H. aurantiae simili, sed anfractibus superne striatis ; colu- 

 mella sub-angulata. 



Our first two figures of this shell were copied from those given 



