PARTULINA, MOLOKAI. 39 



P. dwightii, which is usually more solid, often larger, with a 

 white columella and lip. Newcomb's description of the color- 

 pattern is not quite clear, owing to the failure to place a comma 

 after the word "bands' in his original description, reprinted 

 above. This was rectified by him in the P. Z. S., where in 

 both Latin and English versions he makes it plain that it is 

 only the "undulations' (or axial stripes) which are restricted 

 to the third whorl. Sixteen specimens in coll. A. N. S. P., in 

 two lots received from Newcomb, agree well with his account. 

 Some of them are figured on plate 8, figs. 15 to 18. It will be 

 seen that the color-pattern varies widely. In some specimens 

 the last two whorls are rich brown, uniform or varied with 

 spiral bands and lines, the spire paler above, suture white- 

 edged, lip and columellar fold brown. Other shells have a 

 light cream ground on which there are few or many brown 

 spiral lines and bands, or in place of them there may be dark 

 narrow streaks. The last embryonic whorl may have oblique 

 or zigzag stripes, but they are often lacking (pi. 8, figs. 15-18, 

 from shells received from Newcomb). Newcomb's type figure 

 is copied, pi. 8, fig. 14. 



Length 25, diam. 14, aperture 13 mm. 



Length 21, diam. 13, aperture 10.5 mm.; 6i whorls. 



Length 24.5, diam. 13, aperture 11.3 mm.; 6J whorls. 



There is a continuous intergradation between the dark brown, 

 rich orange-brown and longitudinally lineolate forms, all hav- 

 ing a snowy and usually rather broad subsutural band. Often 

 the tawny, longitudinally lineolate form has white or pale 

 brown spiral bands (figs. 15, 16), producing, when the bands 

 become numerous, the pattern shown in Newcomb's figure 

 (copied in pi. 8, fig. 14), which I take to be the typical pattern, 

 though Mr. Sykes has figured one of the dark, bandless shells 

 as typical. It is no great step from some shells of this pattern 

 to P. dwightii concomitans. 



In the Cooke collection there are white specimens with the 

 lip very pale brown, apical whorls fleshy (pi. 7, fig. 17), with 

 others showing traces of the brown bands on the base and latter 

 part of the last whorl. A peculiar shell has narrow brown lines 

 near suture and on periphery, and a patch at the axis, on a 



