6o 



il. Solariellopsis pagodiformis n. sp. PI. V, fig. 2. 



Stat. 178. 2°4o'S., 128 37. 5 E. 835 M. Blue mud. 1 Spec. 



Stat. 300. io°48'.6S., I23°23'.i E. 918 M. Fine grey mud. 2 Spec. 



Shell conical, with convex base, nacreous, covered by a very thin, transparent layer of 

 yellowish shelly matter. The largest specimen has 8 whorls. Nucleus white, smooth, occupying 

 about one whorl. The next 3 whorls are straight on their upper part and separated from the 

 lower part of each whorl by a sharp keel, crossed by rather distant radiating ribs, which form 

 sharp tubercles in crossing the keel, and on the third whorl also near the suture. These ribs 

 become obsolete, and disappear on the last whorls, which are smooth on their upper surface, 

 which is only very slightly convex, with a spiral row of spinous nodules, at a little distance 

 from the canaliculate suture, and a strong keel at the periphery; below this keel the whorls are 

 excavated, so as to form with the channel of the next whorl, a rather wide, deep channel, over 

 which the keel projects, producing the pagodiform shape; of the spinous nodules, the largest 

 specimen has 25 at the keel, and about 30 near the suture. The base is rather convex, with 

 a small umbilicus, bordered by a rather strong, crenulated, spiral rib, between this and the 

 peripheral keel run 4 spiral lirae, which are more or less beaded, the outer one nearest to 

 Jthe keel, borders the concave inferior space of the upper whorls, and on this spiral runs the 

 suture, which is slightly crenulate. Aperture subquadrangular, outer and basal margins sharp, 

 irregular by the ends of the spirals; columella nearly straight, with a distinct angle where it 

 oins the basal margin •, this angle is caused by the umbilical rib, its upper part is slightly 

 refiected over the umbilicus and covers it partly. The umbilicus is somewhat roughened by the 

 lines of growth. The whole shell is covered with irregular, interrupted, hairlike lines of growth, 

 visible only uncler a lens. Interior of aperture smooth. 



Alt. 14 1 /., diam. maj. \i x \ v Apert. alt. 6, lat. 6 Mill. 



The three specimens of this species vary slightly in the lirae of the base; in the largest 

 specimen from Stat. 300, the outer one is regularly beaded or crenulate; the inner less so, 

 especially near the aperture, the two intermediate ones are nearly smooth; the smallest specimen, 

 from the same locality, has them all beaded, though the 2 d and 3 d are smoother near the 

 aperture, and in the only specimen from Stat. 178, the lirae are nearly smooth, only that next 

 the umbilicus is obsoletely beaded. 



This species has in outline some resemblance to Solariella lissocona Dall, but may be at 

 once distinguished from that species, by its excavated sutural area and the narrower umbilicus, 

 in the first particular it resembles S. mogadorensis Locard, but is quite different in shape and 

 in many other respects. Solariella oxycona Smith, which has been figured : ) may be allied, but 

 is according to the description, still more conical, and it has 110 indication of a canaliculate 

 suture. The species seems also closely allied to Basilissa ottoi (Phil.) var. CJuini v. Martens 

 (Die beschalten Gastrop. der deutschen Tiefsee-Expedition 1898 — 99, pag. 127, PI. 4, fig. 19), 

 but it is quite different from Philippi's original figure (Fauna Moll. Regni utriusque Siciliae, 

 pi. 28, fig. 9) of this Sicilian fossil; from the figure of v. Martens (1. c.) it differs especially by 



1) lllustr. Zool. Investigator, Moll. Part III, Tl. XII, fig. 6. 



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