PARTULA, MOOREA. 203 



sometimes nearly white, and the stripes are 'brown-corneous or 

 even, unequal and unevenly spaced. The sculpture consists 

 of spiral incised striae which are rather widely spaced, and 

 typically are distinct on the last whorl. 



This type of shell is further modified by the development 

 of spiral bands; sometimes only one, at the periphery, the 

 base of the shell often chestnut-colored, and again two bands, 

 one above, the other below the periphery (pi. 28, fig. 8; pi. 27, 

 fig. 6). Specimens with oblique streaks only, with one and 

 with two bands, occur together in Grarrett's sendings, and 

 apparently are mingled in the same colonies. The spiral 

 striation is usually subobsolete on the upper part of the last 

 whorl in these shells, which are what Pease named in MS. and 

 Smith described as P. alternata. The preceding forms are 

 what Garret t alludes to as found in Oahumi valley. Com- 

 paring this race with vexillum, he writes: ''The Oahumi 

 shells are usually a trifle smaller, not so frequently dentated, 

 and are much more conspicuously strigated than the Vaianai 

 shells. The spiral bands, of which there are one or two, sel- 

 dom three, on the body- whorl, are very frequently interrupted, 

 which, with the conspicuous strigations, gives the shell a some- 

 what tessellated appearance. All the color- varieties alluded 

 tOjin my remarks on the Vaianai shells are also found in 

 Oahumi, but the uniform dark-colored ones are more fre- 

 quent, besides one of a uniform white color, not decorticated, 

 of which I took three examples. 



1 'So far as I can ascertain, there has been no figure pub- 

 lished of Pfeiffer's strigosa. He gives the Admiralty Islands 

 as its habitat. There are no species of the type he describes 

 found in the western Pacific. It is undoubtedly a Society 

 Islands species, and I fully agree with Dr. Hartman in re- 

 ferring it to the shells under consideration. ' ' 



Further Oahumi color-forms are represented in pi. 28, figs. 

 1, 2, 3, 4, the lot from Garrett. They are chestnut with light 

 streaks and a white suture, the spire flesh-colored (fig. 3), the 

 same with a pale girdle (fig. 2), or line (fig. 1), at the peri- 

 phery, or there may be two white zones, one below the suture, 

 the other in the middle of the basal slope (fig. 4). 



