ACHATLNELLA VULPINA. 217 



Very often the color fades to yellow at the suture, or the 

 change to yellow may be abrupt, as in pi. 39, fig. la, which 

 agrees with Ferussac's variant &. This leads to the pattern 

 figured by Reeve as A. castanea, which is represented by pi. 

 39, fig. 2, Gulick coll., from the Pauoa side of Nuuanu. The 

 same form is also found in Pauoa, pi. 40, fig. la. 



A. vulpina extends eastward to Makiki valley, where the 

 chestnut or blackish form with yellow band above occurs in 

 the northern branch, together with the dunkeri pattern of 

 producta (L. A. Thurston and Irwin Spalding). Some of the 

 shells have the rim within the lip rather thick. A. v. olivacea 

 has been taken in Makiki by Gulick, and recently by Mr. 

 Thurston in the middle branch. On the Manoa base of 

 Tantalus Mr. Thurston found olivacea associated with pro- 

 duct a , johnsoni and dunkeri. 



Pauoa. The prevalent form is the adusta pattern (pi. 40, 

 fig. 2, copy of Reeve's figure; figs. 1, Gulick coll.). The base 

 is chestnut, or Isabella, with a chestnut band ; above the peri- 

 phery it is deep colonial buff or ecru-olive, sometimes more 

 or less suffused with chestnut or green. There is a narrow 

 band below the suture, usually blackish chestnut, rarely 

 russet. Probably Reeve's type of adusta was from Pauoa 

 valley. The castanea pattern (pi. 40, fig. la, Pauoa, coll. by 

 Gulick) is also found. 



The adusta pattern of Pauoa and the slope of Tantalus is 

 a transition form to A. steivartii. In this borderland the dis- 

 tinction between the species is vague, and I am unable to 

 decide upon such forms as pi. 38, figs. 20. Fig. 21 of the same 

 plate I consider a steivartii, as no vulpina is dextral. When 

 the olivacea pattern occurs in colonies of such shells, one 

 may safely pronounce them vulpina. 



In the northeastern head of Nuuanu valley there is a local 

 form of vulpina which has been described by Mr. Baldwin as 

 A. ernestina. It is rather large and capacious typically (pi. 

 39, figs. 3 to 6), but varies so much in size and width that no 

 definite line can be drawn. Fig. 4 is one of Mr. Baldwin's 

 figured cotypes. Figs. 3, 3a are from one tree (Drac&na), 

 taken by Dr. Cooke. The shell is either yellow, deepening to 



