222 ACHATINELLA VULPINA. 



colony on the central ridge. Out of about 300 shells in Mr. 

 Spalding 's no. 666, two show bands like longispira and two 

 have a brown band above the periphery in addition to the 

 sutural band, which is present in every specimen. 



Elsewhere the suturalis pattern has been seen only from the 

 Western ridge of Kahauiki, where a few occur in the hybrid 

 colony of that ridge, probably having spread thither from the 

 vigorous colony of the central ridge. One is shown in pi. 40, 

 fig. 10a. 



An individual fluctuation having a very unusual analoga 

 pattern, from the Bishop Museum collection, is figured on pi. 

 40, fig. lOe, dark above, with faintly yellow base. A very 

 similar color-form has been found by Mr. Theodore Cooke in 

 Nuuanu valley on the east side. 



Kahauiki forms the eastern limit of dextral shells of the 

 vulpina series. The western analoga pattern also finds here 

 its eastern limit, at least in the typical development of the 

 pattern. 



Moanalua valley has forms resembling those of central Hal- 

 awa and of the western ridge of Nuuanu, such as the forms 

 shown in pi. 39, figs. 12, 13 and pi. 40, fig. 5&, 5c (oUvacea) ; 

 also longispira pattern (pi. 40, figs. 11, lla), analoga pattern 

 (pi. 40, fig. 115) and various others (pi. 40, figs, lie, d, e.). 

 Dextral specimens are rare. All of the above from a lateral 

 ravine near the top of the southern ridge of the valley, col- 

 lected by Dr. Cooke (pi. 40, figs. 11 to lie). 



In the northern valley of Moanalua, near the head, there is 

 a large colony of quite small shells, length 14 to 17 mm. The 

 chief constituent is virens of many shades, but the analoga 

 pattern appears occasionally, and rarely the longispira pat- 

 tern (pi. 40, figs. 12, I2a, coll. by Irwin Spalding; fig. 126, 

 coll. by Dr. Cooke) ; also shells resembling figs. 7, 7c, 15a in 

 coloration. This somewhat dwarfed race is comparable to the 

 forms from the bottom of upper Nuuanu. A. lorata from the 

 same place is also dwarfed. Large series of these diminutive 

 shells in the collections of Spalding, Cooke and Thurston 

 show that whatever factor it is in the valley-floor environment 

 which causes diminution of size, does not affect the produc- 

 tivity of the snails. 



