278 AMASTRA, MOLOKAI. 



brown behind the lip. Embryonic whorls slightly convex, 

 the first very finely striate, the second finely plicatulate below 

 the suture, becoming striate in the middle ; following whorls 

 sculptured with growth-strige. Outer lip thin. Columella 

 purplish, bearing a rather strong, thin lamella. 



Length 11.8, diam. 6.9, aperture 6 mm. ; whorls 5%. 



Molokai : Type 2050, C. M. Cooke coll. 



This species resembles A. petricola by having an opaque 

 white band, but it differs in shape, etc. The sculpture of the 

 second whorl is coarser than in petricola. It is a broader 

 shell than A. tricincta, which is rather closely related. In 

 general shape the shell is not unlike A. rustica G-ulick. The 

 type, and another specimen in Cooke coll., are probably not 

 fully adult. Borcherding's pi. 10, fig. 22, from Kamalo may 

 be this species. It does not seem to be A. petricola. 



Section HETERAMASTRA Pilsbry (p. 283). 

 82. A. PERVERSA n. sp. PI. 49, fig. 5. 



Shell sinistral, oblong-turrite, rather solid. Spire a trifle 

 contracted near the summit. Embryonic whorls delicately 

 costulate as in A. Iccva; following whorls having subobsolete 

 growth-wrinkles, less developed than in A. lava. Aperture 

 small, somewhat thickened within. Columellar lamella re- 

 ceding, small and oblique. Length 11.5, diam. 5.5, aperture 

 4.3 mm. ; 6y 2 whorls. 



Molokai : Halawa, near the eastern end of the island, fossil 

 (D. Thaanum). Type in Bishop Museum. 



This shell is very 'Closely related to A. lava of East Maui, 

 differing only in being smoother and in having whorls of 

 slightly smaller caliber about one more in shells of equal 

 length ; the aperture therefore smaller. Whether these dis- 

 tinctions will hold in further specimens remains to be seen. 

 Only one example, collected by Mr. D. Thaanum, has been 

 examined. The dilated columellar margin is broken in the 

 figured type. 



00. A. HUTCHINSONII Pease. PI. 49, figs. 3. 4. 

 See species no. 89. 



