PLATE VIII —IX 



DoLiuM melanostomum, Nobis. 



Habitat, Friendly Islands. 



Shell very large, ovate-globose, pretty light, very ventricose, ridged trans- 

 versely with numerous convex ribs, alternated by other ribs, about two-thirds 

 smaller, sunken between the larger ribs. The furrows which separate them are 

 also sunken, and very distinct. Suture channeled ; spire somewhat elevated, 

 formed of five rounded convex whorls ; the lower one forms of itself almost 

 the whole of the shell. The aperture very large, of a bright coffee color within, 

 and exhibits elevated transverse ribs corresponding to the external depressions. 

 The right lip is a shining black, or nearly so, terminated by a festooned and den- 

 ticulated border. The columella is entirely covered with a shining coffee-co- 

 lored enamel, through which appear the transverse ribs ; it spreads off from the 

 columella towards the base, and forms a large umbilicus. The base of the co- 

 lumella and the five first ribs, which are closer together than the others, are of a 

 dark reddish brown. The whole surface of the shell is of a pale brown color, 

 with a few white spots on the face of the shell, and also on the second whorl of 

 the spire. The right lip is colored dark brown, externally, for about three- 

 fourths of an inch, forming the black margin in plate IX. The whole surface is 

 also marked by numerous longitudinal striae. It measures seven inches and 

 three quarters in its transverse diameter, and nine inches in length. 



Remarks. — This splendid shell was sent me about two years since from Nan- 

 tucket. It was brought in there by a whaler, and was obtained at the above 

 locality by the natives, who were diving for shells. It was the only one found, 

 and has excited the admiration of every beholder by its beauty, size, and singu- 

 larity of construction. It not answering to any description in Mons. Kiener's 

 " Iconographie des Coquilles Vivantes," a work now in course of publication, 

 and in which a monograph of the genus Dolium has appeared, I have no doubt 

 that it is a new species, and one which surpasses all the others in splendor. 



