394 PROCEEDINGS OF THE ACADEMY OF [PaRT II 



ginning. The second whorl is convex, weakly ribbed; third and 

 later whorls are swollen and subangular below the suture, then flat- 

 tened with sculpture of large, well-spaced, axial ribs, the concave 

 intervals finely striate, with in some places the faintest traces of 

 spiral striae also. On the last whorl there are eleven ribs, on the 

 penult ten. On the dorsal part of the last whorl the ribs disappear 

 towards the base. The small aperture is ovate and oblique, with 

 continuous peristome and a strong submedian fold on the inner 

 margin. 



Length 2.35, diam. 0.83 mm.; slightly over 6 whorls. 



Type no. 3016 A. N. S. P. 



Odostomia (Chrysallida) dulcis Pils, and Johns. Plate XVIII, fig. 7. 

 Proc. A. N. S. Phila., 1917, p. 182. 



MELANELLIDAE. (EuUmidae) 



Niso grandis Gabb. Plate XXXIV, flg. 17. 



Niso grandis Gabb, Trans. Amer. Philos. Soc, xv, 1873, p. 227. 



This shell is represented by a specimen of 4 whorls, the upper 

 part and the last half whorl wanting. The remaining whorls a-^e 

 a trifle more convex and shorter than the corresponding part of 

 Niso willcoxiana Dall, indicating a distinct though allied species. 

 The length is 19.3, diam 12.4 mm. 



Type no. 3018 A. N. S. P. 



Niso minuta Gabb. Text-flg. 30. 



Niso minuta Gabb, Trans. Amer. Philos. Soc, xv, 1873, p. 227. 



A single example, no. 3019. The 6 whorls are just perceptibly 

 convex. The last three have slender white axial lines, which appear 

 to be very slightly raised on the pale gray ground. There is a strong 

 keel about the umbiUcus, but none at the periphery. 



Length 1.85, diam. 0.95 mm. 



Further specimens are needed to show whether it attains a greater 

 size. 



Melanella astuta Pils. and Johns. Plate XXXV, flg. 7. 



Proc. A. N. S. Phila., 1917, p. 182. 



Melanella gabbiana Pils and Johns. Plate XXXV, flg. 6. 



Proc. A. N. S. Phila., 1917, p. 183. 



Strombiformis sarissiformis Pils. & Johns. PI. XXXV, flg. 9. 



Proc. A. N. S. Phila., 1917, p. 183. 



The aperture is wider in the unbroken adult stage than in the 



