MUSEUM OF COMPARATIVE ZOOLOGY. 35 



otherwise stated, being taken from back to front, or from the concave to the 

 convex surface. Max. transverse diam. 2.9 mm. 



Off C. San Antonio, 413 fms. Yucatan Strait, 640 fms. 



This species is most like C. colubridens of Watson (New Zealand, 700 fms.), 

 but has no gibbosity on the concave or (dorsal) side, a less oblit^ue mouth, is 

 more tapered, and moi-e curved up posteriorly. 



Cadulus Agassizii n. s. 



Shell translucent white with more opaque annulations ; shining, destitute of 

 sculpture excepting nearly imperceptible lines of growth, very slightly curved, 

 the dorsum being nearly straight except at the posterior fourth, oral end very 

 slightly tapered, not flattened ; posterior part gently tapering from the anterior 

 third ; anal end rather stout, opening simple, circular; oral end thin, mouth 

 forming an angle of 45° with the axis, simple, quite circular ; the tube with no 

 pronounced gibbosity. Lon. 9.0. Max. lat. 2.0. Oral diam. 1.5. Anal diam. 

 0.75. Max. diam. 2.0 mm. 



Station 5, 229 fms. 



This species resembles C. sanridens Watson, but is three times the size, wants 

 the gibbosity, and has a straighter back. It differs from C. gracilis Jeffreys in 

 size and in wanting the compression, so far as can be decided in the absence of 

 a specimen or figure of Jeffreys's species. The proportions are different from 

 those of V. Pandionis Y- and S., of which the mouth is described as elliptical. 



Cadulus lunulus n. s. 



Shell translucent white, smooth, destitute of sculpture ; dorsum nearly 

 straight, slightly inflated near the middle ; oral end contracted, not flattened, 

 and more slender at the mouth than the posterior end ; the shell largest in the 

 middle, and tapering neaily equally to both ends, apertures simple, circular, 

 the oral one oblique and quite contracted in proportion to the rather stout 

 form of the shell, which, Vjut for the curve of the convex side and extreme 

 ends, woidd be nearly evenly fusiform ; there is no gibbosity, and, though the 

 anal aperture is the larger, it seems unbroken. Lon. 6.0. Oral diam. 0.75. 

 Anal diam. 0.87. Max. diam. 1.5 mm. 



Station 2, 805 fms. 



Most like C. simillimus Watson, from which it differs in its more even half- 

 moon shape, and proportions. 



Cadulus cucurbitus n. s. 



This little shell is perhaps best described by saying that in form it is about 

 midway between C. ohesus Watson and C. tumidosus Jeffreys, being larger than 

 the former and more evenly tapered from the middle than either. It wants 

 the ledge within the aperture at both ends, is polished, translucent, and with- 



