DALL: MOLLUSCA AND BRACHIOPODA. 305 



whorls, followed by five subsequent whorls ; spire acute, whorls moderately 

 rounded, the last much the largest ; sculpture on the early whorls decussate by 

 fine transverse riblets, strongest near the suture, and flattish spiral tiireading; 

 later the whorls are polished, smooth, except for lines of growth and narrow, 

 distant, sharp grooves ; suture with a narrow channel ; aperture long, narrow, 

 ■with a shallow narrow sinus behind and a deep siphonal sulcus in front ; outer 

 lip thickened, flexuous, obsourely lirate behind, body with a thin callus ; pillar 

 white, concave, with a prominent margin, shorter than the aperture. Operculum 

 narrow, elongate-oval, with an apical nucleus. Height of shell, 31.5 ; of last 

 whorl, 24.5 ; diameter, 13.0 mm. 



U. S. S. " Albatross," station 3390, in the Gulf of Panama, in 56 fathoms, 

 sand, temperature 02°. 6. U. S. N. Mus. 122,009. 



Owing to the fact that the accessible species referred to Truncaria were all 

 generically different from the present shell, and the original type unknown to me, 

 this species was provisionally referred to Cominella in my preliminary diagnosis. 

 Further study led to the discovery of its true relations. 



VOLIJTOPSIIJS MbRCH. 

 Volutopsius? amabilis Dall, n. sp. 



Plate 11, figure 9. 



Shell decollate, subcylindric, with an apparently blunt spire, whitish, with pale- 

 brown, dull periostracum, and about four whorls, exclusive of the lost nucleus ; 

 suture distinct, not channelled, the whorl slightly constricted iu front of it ; axial 

 sculpture only of faint lines of growth ; spiral sculpture of (on the penultimate 

 whorl about seven) weak, narrow, channelled, incised lines, with flat, wider 

 interspaces and a still wider, smooth space between the first channel and the 

 suture ; the interspaces are narrower and somewhat rounded near the canal ; 

 aperture lunate, outer lip somewhat varicose, simple, entire, vertical ; body with 

 a smooth callus extending on to the short, slightly twisted pillar ; canal very 

 short, wide, not constricted ; operculum short, ovate, with the nucleus near but 

 within the apical margin. Lou. of last two whorls, 10.5 ; of last whorl, 8.5 ; of 

 aperture, 6.0 ; max. diam. 5.2 mm. 



U. S. S. "Albatross," station 3392, Gulf of Panama, in 1270 fathoms, hard 

 bottom, temperature 36°.4 F. U. S. N. iMus. 123,008. 



This curious Uttlc shell is too imperfect for final decision as to its place in the 

 system. It has a distant resemblance to Truncaria, but the form of the operculum, 

 as well as the peculiar blunt spire, remove it from tiiat genus. It resembles as 

 much as anvthing the young shell of a species of Bcriugius. The operculum is 

 not Columbrlloid or Purpuroid. 



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