28 NATICA. 



ing longitudinal stripes ; callus slight, partly covering the umbil- 

 icus from above. Length, 16 mill. 



Hob. unknown, 



M, Recluz is of opinion that the operculum will prove to be 

 corneous. 



N. LIMBATA, d'Orb. PL 8, fig. 50. 



Thin, smooth, reddish or light purplish, white around the base, 

 and white lined at the suture; umbilicus narrow. 



Length, 16 mill. 



Bay of San Bias and Mouth of Rio Negro, Patagonia. 



I am not acquainted with either this or the following species. 



N. ISABELLEANA, d'Orb. PL 8, fig. 51. 



Reddish brown, smooth, thin ; umbilicus narrow. 



Length, 13 mill. 



Maldonado, Uruguay. 



Philippi remarks that the specimen figured and described by 

 d'Orbigny is probably worn and has lost some of its markings, 

 as he had seen a Brazilian shell, with four bands, and longitu- 

 dinal flames which might well be referred to this species. 



N. COLLARTA, Lam. PL 8, figs. 54, 52, 53, 49. 



Whitish, with irregular, interrupted chestnut streaks, not 

 extending to the base, slightly flattened at the suture, and milk- 

 white, bearing fewer, larger sagittate chestnut markings ; umbili- 

 cus with somewhat inferior entering callus ; interior tinged with 

 chestnut. Length, 1-1-25 inches. 



W. Africa. 



N. labrella, Lam.; N. Gambiae, Recluz (fig. 53), an old thick- 

 ened example ; and N. obstructa, Menke (fig. 49 bis) a faded 

 specimen, are synonyms. One of the figures of labrella given 

 by Philippi in Kiister (fig. 52) also represents an individual 

 denuded of color markings. 



N. ELEN.E, Recluz. PL 8, figs. 55, 56. 



Depressed, inflated, spire small, suture well impressed, closely 

 plicately ridged above and below between the growth grooves, 

 the middle of the body-whorl with incised growth lines only ; 

 umbilicus very large, with an inferior entering callus ; whitish, 



