ACHATINELLA LEUCORRAPHE. 301 



to more straightly conic with longer spire, as shown in the fig- 

 ures. It is often subperf orate. Mr. Baldwin's original speci- 

 mens, from the Waimano slope (at that time reached from 

 the valley) were dextral, with the upper surface buff. One is 

 figured, pi. 57, fig. 15 ; but among others obtained by Dr. 

 Cooke at the same place there are also some sinistral shells. 

 At the top of the ridge the cookei colony reaches to the trail 

 at the summit, but not beyond it, and is very narrow the 

 matter of a hundred feet or so alongside the trail as I remem- 

 ber. It is longer in the other direction, extending several 

 hundred yards down a small spur. This small colony is the 

 only place A. t. cookei has been found. At the upper limit 

 of the colony the specimens are all sinistral (20 in coll. A. N. 

 S., 63 in Spalding coll.). In this sinistral lot from the upper 

 edge of the colony, the peristome is brownish-vinaceous. The 

 black base is produced by coalescence of bands. The bicolored 

 stage may begin as early as the beginning of the fifth whorl, ' 

 but is sometimes as late as the last half of the last whorl ; the 

 bands appearing a little earlier. 



A. t. cookei is now recognized by Hawaiian conchologists to 

 be a local race of the many-banded form simulacrum, oc- 

 curring immediately above it on the crest of the Waimano- 

 Manana ridge. Its resemblance to A. mustelina bicolor is 

 purely adventitious. The parent stocks of the two were cer- 

 tainly very unlike. "Named in honor of Hon. 0. M. Cooke, 

 by whose sons the shell was discovered/ 



35. A. LEUCORRAPHE (Gulick). PL 59, fig. 8. 



"Shell dextral, shortly ovate-conic, striated with growth 

 (but scarcely with spiral) lines; gray, ornamented with irre- 

 gularly interrupted dark cinereous streaks and a few indis- 

 tinct, white, spiral lines ; suture broadly margined with snow 

 white ; whorls G 1 /^ ; apex blackish, first four whorls white, 

 nearly flat, the rest convex ; aperture small, somewhat ear- 

 shaped, white ; peristome slightly dilated and thickened 

 within ; columellar fold large, rosy. Length 19, diam. 12 mm. 



"Var. Shell ovate-conic, regularly streaked with dark 

 gray and cinereous; spire straightly conic. [This var. belongs 

 to A. valida.] 



