300 ACHATINELLA TURGIDA. 



with a very pale buff ground, variously banded or lineate ; 

 also a melanistic form in which the first 2% whorls are white, 

 next whorl with bands beginning buff, deepening to chestnut, 

 and then to uniform black on the last two whorls. PL 56, 

 figs. 13 to 13&. This black form resembles the black turgida of 

 the mottled colonies westward except in the late embryonic 

 and early neanic stages, which have the banding of simul- 

 acrum. It is not so rough a shell as A. byronii nigricans, the 

 surface being polished and minutely striate as usual in A. 

 turgida. Moreover it differs from nigricans by having the em- 

 bryonic whorls more conic, with the suture not at all im- 

 pressed, while in nigricans the embryo is lower, wider, with 

 more convex whorls parted by a noticeably impressed suture. 

 When studying Mr. Spalding's collection I noted that some 

 specimens in one of his Waimano-Manana lots have a blackish 

 apex. Others of the lot are typical simulacrum, with white 

 apex, and in one the whole base is black. The variation in 

 color of the apex in this lot calls for further study. 



. A. TURGIDA COOKEI Baldwin. PL 57, figs. 15 to 17. 



The shell is dextral or sinistral, with the last whorl bi- 

 colored, black or chestnut-black below the periphery, white, 

 light buff or tawny above, usually darker below the suture; 

 peristome livid pink (or brownish vinaceous) ; embryonic 

 whorls white or ivory. 



"Length 21, diam. 15 mm.' (Baldwin). 



Length 19, diam. 14 mm. (Cotype). 



Length 18, diam. 13.2 mm. (Cotype, Proc. A. N. S., pi. 10, 

 f. 15). 



Length 20, diam. 13 mm. ; GVs whorls. 

 * Animal : mantle dark slate with a narrow brown band en- 

 circling the outer edge. Superior portion of foot light brown, 

 mottled with slate, under surface dingy white' (Baldwin). 



Waimano-Manana ridge at about 1,800 ft., extending sev- 

 eral hundred yards down the Waimano slope. 



A. cookci BALDWIN, Proc. A. N. S. Phila., 1895, p. 220, pi. 

 10, f. 15 (July 2, 1895). 



Tn shape this form varies from short with swollen last whorl 



