258 AMASTRA, MOLOKAI. 



whorls form a rather acute, conic summit, the first half whorl 

 being smooth, rather coarse, low axial ribs then appearing 

 weakly. The second whorl has rather strong, arcuate ribs, 

 rather wider than their intervals, and split or weak near the 

 lower suture; on the next whorl the ribs are finer, and weak 

 below the middle of the whorl, or split into striae. There 

 seem to be 3% embryonic whorls, which in outline are nearly 

 flat. 



The following whorls are moderately convex, with sculpture 

 of somewhat thread-like striae, though in places they are low 

 or partly effaced. The columellar fold is rather small and 

 very oblique. Outer lip thin. 



Length 28.3, diam. 15, aperture 13.5 nun. ; 7 whorls. 



Length 30.5, diam. 13.7, aperture 13 mm. ; iy s whorls. 



The size varies a good deal. One shell from the Gulick 

 collection measures, length 25, diam. 12.5 mm. ; 7 whorls. An- 

 other has a spirally lengthened callous ridge upon the parietal 

 wall, revolving into the aperture. 



Some of the above-mentioned localities may pertain to the 

 following variety : 



69a. Var. wailauensis n. v. PI. 39, figs. 13, 14; pi. 27, figs. 

 1, 2. 



Larger and more robust than violacea, the striation weaker ; 

 dull gray or fleshy-gray, with shreds of dark brown cuticle 

 chiefly on the last whorl. 



Length 38, diam. 19, aperture 16.2 mm. ; 8 whorls. 



Length 34.6, diam. 18.5, aperture 16.3 mm.; 7% whorls 

 (no. 104670). 



Length 31, diam. 16.5, aperture 14.8 mm. ; 7% whorls. 



Length 27, diam. 14.5, aperture 12.8 mm. ; 6% whorls. 



Wailau (Borcherding, Thaanum). Type no. 104670 A. N. 

 S. P. 



Borcherding 's figures, copied in our pi. 27, figs. 1, 2, repre- 

 sent Wailau examples of this variety. A very large specimen 

 in the Bishop Museum, collected by Mr. Thaanum (pi. 39, fig. 

 13) has no columellar lamella, probably on account of old 

 age. Two other shells have calluses on the parietal wall such 

 as are mentioned under violacea. 



