108 THE NAUTILUS. 



folds, ascending obliquely from near the base; no callus within; 

 lamellae and plicae 6; parietal rather long and curved; parallel with 

 it is a thin, lamelliform angular; columellar and inferior columellar 

 rather small, short, the latter near the base; palatals long, the lower 

 deep-seated, ending close to the beginning of the upper, one appear- 

 ing to be a continuation of the other. 



Alt. 1.6, diam. 0.9 mm. 



Soft parts not seen. 



Woodland, Aroostook county, Maine, collected in 1896 by Mr. 

 Olof O. NyJander, in whose honor the species is named. I liave two 

 specimens on hand, the types (No. 1075 of my collection of North 

 American Pupidce); a few more are in the collection of Mr. Nylander. 

 Ever since '96 the form was regarded as distinct, but not publi.-^hed. 

 The two specimens are alike, mature and perfect, and cannot be 

 deformed ones of some other species. In appearance and surface 

 stria; they are somewhat like V- gouldii Binn., but otherwise the 

 shell is quite different. In its shape, with the narrowed last whorl, 

 it somewhat resembles V. oscariana St., but the lamellae and plicae 

 are very different. 



BiFIDARIA CLAPPI n. Sp. 



Shell glossy, colorless to milky-whitish, perforate, cylindrical in 

 the lower 3-4 whorls, conical or subconical above, with a rather 

 acute apex; whorls 6^-7^, the upper ones rather narrow, the lower 

 ones broader and less convex, the last moderately large, ascending 

 at the aperture, somewhat narrow but rounded at the base, slightly 

 flattened over the palate; surface shining, with slight irregular to sub- 

 regular striae; aperture nearly oval, margins approximate; peristome 

 everted, not thickened, but there is a slight to rather strong white 

 callus in the palate; lamellae and plicae: parieto-angular distinctly 

 complex, rather long, moderately elevated, connecting with the peri- 

 stome near its outer upper terminus (much as in B. armifera), the 

 spur' of the parietal moderately large; columellar axial spiral, with 

 the lower end nearer the aperture, thicker and rather abrupt, or 

 somewhat bifurcate; " basal " (inferior columellar) slight or wanting; 



^ In B. armifera and clappi, near the inner end of the parietal lam., there is a 

 process, or "spur," outward, that is, towards the periphery, at nearly right 

 angles, smaller or larger, generally visible in front view. So far it has been 

 seen in no other species ; but in £. contractu there is a protracted, curved part, 

 lower than the rest of the lam., and not visible in front view. 



