332 



ception of P. milium, and is most readily distinguished 

 by its short, conical form. The five specimens examined 

 all presented the crowded, thimble-like impressions, un- 

 der a magnifying power of twenty diameters. I think it 

 is the only American species which has a tooth revolving 

 within the shell, on the penultimate whorl. [G.] 



b. Tentacles apparently two only. VERTIGO. 



9. VERTIGO GOUL.DII, BlNNEY. 



PLATE LXII. FIGURE 2. 



V. testa minuta, ovato-cylindracea, sub-castanea ; anfract- 

 ibus plusquam quatuor ; apice obtuso ; apertura sub-cordata, 

 bilobata, dentibus quinque armata ; labro sub-reflexo. 



SYNONYMS AND REFERENCES. 



Pupa Gouldii, BINNEY, Proc. Bost. Soc., 1843. I. 105. 



GOULD, Boston Journ. IV. 352, pi. 16, f. 9. 

 PFEIFFER, Monog. Helic. Viv. II. 358. 



DESCRIPTION. 



ANIMAL with two tentacles only ; black above, foot 

 gray, tapering posteriorly, and rounded at the extremity ; 

 carries the shell at an angle of about forty-five degrees. 



SHELL light chestnut, cylindrical ovate ; whorls rather 

 more than four, ventricose, the last occupying nearly one- 

 half the length of the axis ; aperture lateral, composed 

 of two unequal curves meeting in the centre of the outer 

 lip, with five prominent, white teeth ; namely, one upon 

 the transverse margin, two upon the umbilical margin, 



