332 LAMINELLA, OAHU. 



volution is convex but the increase by growth may vary from 

 a straight spiral to one with concave sides, the last volution 

 is as a rule gibbous but may as in one shell, no. 1042 Gul. 

 coll., from Ahonui, verge on the sub angular. 



"The eolumella varies excessively in one large shell, no. 

 1042 Gul. coll., from Ahonui, it is widely open and the aspect 

 of the base is quite distinct from that of the majority of the 

 forms in which it has long narrow elongated perforations. 

 In a certain number of shells a limited number it may be 

 almost closed " (Hyatt}. 



The ground-color varies in tint, and in a few examples 

 becomes nearly white. There is a tendency to form a second 

 and even a third columellar fold, as in Amastra turritella, 

 but in an insignificant proportion of the shells examined, 

 and not restricted to those of any special locality. Although 

 this species ranges across the island, from Waianae valley on 

 the southwest to Kahana on the northeast, we note no ten- 

 dency towards local or racial differentiation. Specimens 

 from various places measure : 



Length 18.5, diam. 10 mm. (Waianae). 



Length 17.5, diam. 10.3 mm. (Waianae) . 



Length 21.3, diam. 10 mm. (Helemano). 



Length 21, diam. 11 mm. (Helemano). 



Length 22, diam. 11 mm. (Wahiawa). 



Length 19, diam. 9.8 mm. (Wahiawa). 



Length 22.3, diam. 11.5 mm. (Ahonui). 



Length 21.5, diam. 11.3 mm. (Kahana). 



L. sanguinea has very much the same distribution as Amas- 

 tra spirizona, including nigrolabris. Whether it originally 

 belonged to the Waianae or to the Koolau range is undeter- 

 mined. 



A. ferussaci Pfr. was based upon a shell which had lost 

 the dark markings, either artificially or by weathering. 



Mr. Oleson reports that there are two varieties in Palolo 

 valley, the rose-colored which is found in a little offshoot from 

 the main valley and the paler-colored ones are found in the 

 main valley itself. Their habitat is uniformly on a single 

 plant, the olona, having large succulent leaves, growing 



