194 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 48 
EXPLANATION OF PLATES 
PuatE XLIII 
Fics. 1-4. Hendersonia palmeri Dall, n. g. et sp. Fig. 1, view from below; 
2, profile; 3, specimen with the whorl broken away to show internal 
spiral lamina; 4, view from above; all figures magnified two and one- 
_' third diameters. See page 187. 
PLaTE XLIV 
Fic. 1. Xanthonyx potosiana Dall, n. sp., from above, magnified. See page 
190. 
Fic. 2. The same in profile. 
Fic. 3. Schazicheila palmeri Dall, n. sp., magnified. See page 191. 
Fic. 4. Streptostyla potosiana Dall, n. sp., nat. size. See page 190. 
Fic. 5. Schazicheila palmeri Dall, from above, magnified. This specimen has 
the sinus at the aperture less developed than usual in adults. See 
page IOI. 
Fic. 6. Spherium mexicanum Dall, n. sp., magnified about 5% diameters. 
See page 193. 
Fic. 7. Xanthonyx potosiana Dall, n. sp., from below, magnified. See page 
190. 
