S5 



double; the whole base is covered by radiating very oblique riblets. Umbilicus pervious, funnel- 

 shaped, with 2 spiral lirae, of which the lower one is beaded, and radiating riblike striae, its 

 largest diameter is about Y, of the base. Aperture rhombic; outer margin rather thin, convex, 

 internally lirate, with short folds between the lirae ; basal margin short, convex, internally with 

 a few lirae ; columella broad, concave, with a conspicuous fold near the base and a small denticle 

 above it, its upper part connected to the outer margin by a conspicuous layer of enamel, with 

 thickened margin, and a free ear-shaped projection, covering part of the umbilicus. 



Diam. maj. 12, alt. 8, apert. alt. 3^3, lat. 5 Mill. 



I have located this very peculiar shell in the new genus, on account of its general 

 resemblance with the preceding species; in many particulars it is so much different, that it is 

 superfluous, to insist upon its specific distinctness. 



3. Solariellopsis pulc/ira n. sp. PL IV, fig. 4. 



Stat. 256. 5°26'.6S., i32°32'.sE. 397 M. Greyish green mud. i Spec. 



Shell depressedly conoidal, with nearly flat base, sharply keeled, yellowish-white, with a 

 laro-e umbilicus ; whorls about 6, slightly convex ; nucleus smooth, upper whorls with concentric 

 ribs; on the third whorl they are pointed above, at some distance from the suture, and near 

 the base of this whorl, appears a row of tubercles on a spiral rib. The subsequent whorls are 

 slio-htly concave or canaliculated near the suture, the fourth is sculptured by concentric ribs, 

 with strono-er tubercles at the top, near that depression; on the fifth, the sculpture consists of 

 a row of tubercles and 3 beaded lirae, of which the third, near the keel is the strongest, this 

 keel is compressedly crenulate, the space between suture and tubercles has short, irregular folds. 

 The same sculpture persists on the last whorl, where the tubercles, about 30 in number, are 

 compressed and show a tendency to become double, the crenules of the keel are slightly concave 

 from above to below. Base nearly flat with 5 concentric beaded lirae, the beads bordering the 

 umbilicus are the largest; the whole base is covered with rather regular, riblike striae and very 

 fine microscopic ones, visible also on the upper part of the shell. Umbilicus large, occupying 

 from the base of columella to the opposite side, about "j. of the diameter of the shell, it is 

 funnel-shaped, pervious, its wall spirally striate, with a single, spiral, beaded rib and radiating 

 plicae. Aperture rhombic, probably not quite developed, thin, upper margin convex, basal one 

 nearly straight; columellar margin slightly convex, reflected above, parietal wall with a thin 

 layer of enamel. 



Diam. maj. 13, alt. 6^j,_; apert. alt. 37^, lat. 57„ MiU. 



Resembling the preceding species, but with a much less conspicuous keel and different 

 sculpture, the specimen is apparently not quite adult, and the characters of the aperture are 

 not developed. 



4. Solariellopsis spinulosa n. sp. PL IV, flg. 5. 



- Stat. 159. o°S9'-i S., I29°48'.8E. 411 M. Coarse sand. 2 Spec. 



SheU depressed, with low conical, convex spire; strongly keeled, base convex; yellowish- 



55 



