152 TORNATELLINA. 



(Peel Island) are similar, but none are quite adult. The 

 smallest, length 2.5 mm., shows a triplicate columella. 



Specimens from Ani-jima (Buckland Island) are a trifle 

 more robust (pi. 32, fig. 3, length 2.9, diam. 1.6 mm.), but 

 perhaps are not absolutely full grown. Four or five whitish 

 varix-streaks are visible through the last whorl. A younger 

 (paraneanic) stage is drawn in figs. 11, 12, representing a 

 shell 2.8 mm. long. The columella is biplicate, a strong hori- 

 zontally entering lamella being superposed upon the colu- 

 mellar fold. The parietal lamella is very strong, and the pala- 

 tal rib is crenulate. A second internal palatal rib is visible 

 outside as a whitish streak on the back. 



Figures 8, 9, 12, 2 and 1, represent four successive stages 

 of development, the stages shown on plate 32 being as follows : 



Figures 1 to 6, ephebic (adult) stage. 



Figures 11, 12, paraneanic stage. 



Figures 7, 9, 10, metaneanic stage. 



Figure 8, last embryonic stage. 



It will be noted that some individuals retain the distinctly 

 biplicate columella of the paraneanic stage in the ephebic 

 (fig. 4). 



Var. longa Pilsbry. PL 32, figs. 5 to 10. Differs from oga- 

 sawarana by its longer spire of fully 6 whorls. Length 3.5, 

 diam. 1.6, aperture 1.2 mm. Chichi-jima (Peel Is.), figs. 5, 6, 

 8, 9. The specimens are pale-yellowish, possibly fossil. A 

 young one 2.6 mm. long is drawn, fig. 9. An embryonic shell, 

 removed from one of the adults, measures 0.65 mm. long (fig. 

 8). This has a triplicate columella, as in the neanic stage, 

 but less strongly developed. Figs. 5, 6 are adult individuals. 



Living examples of this race, from Imoto-jima, are repre- 

 sented by the adult form, like fig. 5, and the metaneanic stage, 

 shown in figs. 7, 10, length 2.2 mm. The columella is here 

 strongly triplicate. The palatal rib is smooth ; within the last 

 whorl there is a second rib on the back, visible as a whitish 

 streak externally. 



14. T. BIPLICATA Pilsbry. PI. 37, fig. 3. 



The shell is ovate-pyramidal, thin, fragile, light brownish- 



