26 BOOK OF SPECIES. 



umbilicus peculiarly open ; aperture simple, most 

 minute. B. T. 46. 



H. CRYSTALLiNA. Minute, thin, perforated, 

 depressed, white, shining, and diaphanous. T. 

 42. B. 



CAROCOLLA. 



Orbicular, more or less convex or conoid above; 

 circumference angular and sharp ; aperture 

 transverse, contiguous to the axis of the shell ; 

 outer lip sub-angular, frequently dentated be- 

 low, 



C. ALBiLABRis. Imperforate, convex on both 

 sides, chestnut-brown, with a paler obsolete band 

 on the keel ; six obliquely and slenderly striated 

 whorls ; aperture transverse and ear-shaped, with 

 a white reflected lip. W. 33. 34. 



C. LUCERNA. Orbicular, limbilicated, and 

 somewhat depressed, smooth and whitish ; lip 

 reflected, with two teeth in the inside, and corre- 

 sponding impressions without; diameter IJ. W. 

 33.30. 



C. GUALTERiANA. Imperforate, flat above, 

 convexly turgid, beneath rough, decussated, dirty 

 ash-colour ; spire extremely flat ; lip thin and 

 reflected ; diameter If. W. 33. 44. 



C. MARGiNATA. Umbilicated, obliquely stri- 

 ated, and the spire depressed ; base convex, and 

 the aperture ear-shaped, with a white margin ; 



