TORNATELLINA. 151 



mellae in the Tornatettinida, we look upon the embryo of 

 Lamellina as a form retaining ancestral structures, probably 

 common to most or all of the existing genera of the family 

 before their divergence. 



Japanese Species. 



13. T. OGASAWARANA Pilsbry & Cooke, n. sp. PL 32, figs. 1-4, 

 11, 12. 



The shell is imperforate, ovate-pyramidal, brown, not very 

 glossy, weakly marked with growth-striae. Spire straightly 

 conic, composed of slightly over 5 convex whorls, the last con- 

 vex below, somewhat compressed laterally in its last half. 

 Aperture oblique, ovate; outer lip thin, but within its edge 

 there is a strong callus rib, slightly brown-ftinted, and weaker 

 at the upper curve of the lip. Columella bearing a heavy, 

 white, callous fold, which is produced forward at its lower 

 end, and is either bifid (fig. 4) or nearly simple (figs. 1, 2) 

 within. There is a very deep furrow between the columellar 

 fold and the adjacent basal wall. Parietal lamella usually 

 short, not entering deeply. Length 3.2, diam. 1.7 mm. ; length 

 of aperture 1.25 mm. 



Bonin Islands (Ogasawara-jima) : Minami-jima, types 

 85760 A. N. S. ; also Chichijima, Anijima, Nakano-shima and 

 Imoto-jima (Y. Hirase). 



This common species of the Bonin Islands is closely related 

 to T. siibcylindrica of Guam, in the Marianne group. 



Figs. 1, 2, 4 represent adult shells of the type lot from Mi- 

 nami-jima. In a front view the columellar fold appears 

 nearly simple, broad, heavily calloused, and terminating out- 

 wardly in a strong lobe, foreshortened in this view, fig. 1, but 

 seen partly in profile in fig. 2. In some examples, otherwise 

 similar, the columellar callous is bilobed as seen in oblique 

 'view (fig. 4), by retention of the neanic condition in the 

 ephebic stage. None of these specimens shows pale streaks 

 externally or any other trace of former internal varices. No 

 young specimens were in this lot. Specimens from Nakano- 

 shima, an islet near Muko-jima (or Kater Island), in the 

 Parry group, are exactly similar. Several from Chichi-jima 



