PLATE XVI. 



FIG. I. 

 NERITA PALLIDULUS. 



PALE NERJT, 

 GENERIC CHARACTER. 



Globose. Aperture semiorbicular. 



SPECIFIC CHARACTER 



Semitransparent. Wreaths rather prominent. Mouth semilunar, 

 very patulous. Umbilicus large. 



Nerita Corneus, spira paululum exsCTta. Pallidulus Da Costa, p. 51. 

 Sp. 29. 



Da Costa says *' This species is rare, for I have only received 

 some few shells from the coasts of Kent and Dorset." He also con- 

 siders it an undescribed shell. 



