NATICA. 99 



143. FLUCTUATA, f. 17, 8 oiv ci^by .^—OhUque globosa, griseo- 

 fulva, tenuis, flammis fulvis fluctuatis, all)o marginatis 

 ornata ; apertura maxima, oblique expansa ; labio externo 

 tenui superne depresso ; columella nivea callosa, latiuscula, 

 ad marginem dense castanea. 



144. HELicoiDES, f. 12, Johnson. — Tenuis alba ovata, 

 vix umbilicata, epidermide tenui induta ; spira plus minusve 

 produeta anfractibus ad suturam plauo-excavatis, apertura 

 subpyriformi, columella angusta. — Rather oval, with elevated 

 spire, the whorls of which are slightly excavated near the 

 suture ; columella simple, turned back so as to hide, or 

 nearly hide, the linear umbilicus. Cornea of Moller is said 

 to be wider and more inflated than the typical form, but 

 the species is extremely variable. 



