TORNATELLINA. 145 



Austral Is.: Rurutu (type loc.; Ch. De Gage). Cook's or 

 Hervey Is. Society Is. : not uncommon, and ranges through- 

 out the group (Garrett). 



Tornatellina perplexa GARRETT, Proc. Acad. Nat. Sci. 

 Phila., 1879, p. 24; Journ. Acad. Nat. Sci. Phila., 1881, p. 

 398; ix, 1884, p. 82, pi. 2, f. 23. Tornatellina, bUamellata 

 SCHMELTZ (not of Anton), Cat. Mus. Gotleffroy, v, p. 90. 



The columella is tridentate, there being a high, acute 

 median lamella, and two subequal and much smaller denticles, 

 one above and another below. In adult shells the upper and 

 lower denticles can be seen only in an oblique view in the 

 aperture, as in pi. 34, fig. 12, and pi. 36, fig. 2; but in the 

 young (neauic) stage the three lamellae are noticeable in a front 

 view. This structure separates T. perplexa at once from T. 

 nitida, which is otherwise related. 



Garrett writes : ' ' Some examples have the palatal denticles 

 mounted on delicate, longitudinal lines of callus ; others have 

 the internal teeth so distinct as to give the aperture a ringent 

 appearance. Cook's Island examples sent to the Museum 

 Godeffroyanum were erroneously referred to Anton's T. bi- 

 lamellata, a species twice the size of this. ' ' 



8. T. NITIDA Pease. PI. 36, figs. 3, 7 ; pi. 34, fig. 11. 



The shell is turrite, with straight sides, very thin, clear yel- 

 lowish corneous, rather transparent, glossy, faintly marked 

 with slight growth-wrinkles. Composed of 5y 2 moderately 

 convex whorls, parted by a very narrowly margined suture ; 

 the last whorl convex. Aperture small, oblique. Outer lip 

 simple, fragile. Columella somewhat thickened, sigmoid, 

 spirally twisted, grooved around the insertion, and encircled 

 with a sharp, thin median lamella superposed upon the colu- 

 mellar callus, and so deeply placed that in adult shells it is 

 visible in oblique view only. The parietal lamella is strong 

 and extends inward half a whorl. In the palate there are fre- 

 quently one or two spiral rows of small compressed denticles. 

 Length 3.2, diam. 1.5 mm., aperture 1.1 mm. (Huaheine spe- 

 cimen ) . 



Marshall Group: Ebon Island (Andrew Garrett, type loc.). 



