AURICULELLA, OAHU. 79 



Proc. Bost. Soe., ii, 1845, p. 19. Auriculella armata ANCEY, 

 Bull. Soc. Malac. France, vi, 1889, p. 213. Auriculella pa- 

 tula SMITH, P. Z. S. London, 1873, p. 88, pi. 10, fig. 24.- 

 ANCEY, Bull. Soc. Malac. France, vi, 1889, p. 215. Auricu- 

 lella perkinsi SYKES, Fauna Hawaiiensis ii, Moll., p. 377, pi. 

 11, figs. 17, 18. Auriculella triplicata PEASE, Journ. de Con- 

 chyl., 1868, p. 346. 



This species varies greatly in form, size and color. The 

 typical form (or rather the form which comes nearest to 

 Ferussac's description) is from Pauoa, just back of Hono- 

 lulu. A. perkinsi is slightly larger and more solid than the 

 Pauoa shells, but in form and color-pattern agrees closely 1 

 with the typical auricula. 



The largest adult specimen measured 9.5 x 4.8 mm., the 

 smallest 6.5 x 4.1 mm. Most of the specimens are perforate. 



Bulimus armatus Migh. was undoubtedly from Oahu, as. 

 the colurnellar fold is present ; not from Hawaii as he states. 



The color- variety figured as A. dumartroyi by Souleyet is 

 rather characteristic. This color-variety, with a very broad 

 light band, is only found in the upper part of Nuuanu and 

 Tantalus. From the known localities of other species col- 

 lected during the voyage of the Bonite, there is no doubt that 

 this shell came from Nuuanu, though the measurements are 

 rather large for a shell from this locality. 



A. triplicata Pease is a rather broad form of this species. 

 The deep duplication of the columella is often found in typi- 

 cal specimens of auricula,. Pease's specimens undoubtedly 

 came from Palolo Valley. 



The young of this and the allied species are irnperforate, 

 angular at the periphery of the last whorl, and the columellar 

 fold is strongly developed, rather thin and nearly horizontal ; 

 there are no palatal plicae. 



The different colonies of A. auricula, from Nuuanu, are 

 very interesting. They differ from one another considerably. 

 Some colonies are entirely dextral, while in one only 12 per 

 cent are dextral, the others with varying percents all the 

 way between. . Each colony is remarkably constant in its pro- 

 portions of length to breadth. Usually some one color-var- 



