278 PROCEEDINGS OF THE ACADEMY OF [1893. 



3. V. adela West. : Central Europe ; fossil in Sweden. 

 3a. V. declivis Sterki : Central Europe. 



4. T r . pollinensis Paul. : Italy. 



5. V. costata Mull. : circumboreal ; Australia. 



6. V. albula Sterki : Northern North America. 



7. V. parvula Sterki : North America. 



8. V. tenera Rein h.: China, Japan. 



9. V. patens Reinh. : China. 



10. V. gracilicosta Reinh. : Rocky Mountains. 



11. V. perspectiv a Sterki : North America. 



12. V. cyclophorella Anc. : Western North America. 



13. V. tenuilabris A. Br : Asia ; fossil in Germany. 



14. V. mionecton Bttg. : Western Asia. 



15. V. ladacensis Nev. : Central Asia ; Alaska. 



APPENDIX. 



After this paper had been written, Mr. Wm. H. Dall kindly 

 forwarded me many additional specimens of Vallonia from the 

 National Museum. I would add the following notes upon them : — 



V. pulchella Mull was largely represented from Madeira and 

 Bermuda. The specimens from the latter locality are of a somewhat 

 peculiar form, being composed of only three comparatively large 

 whorls, the umbilicus is first quite narrow, rapidly widening for the 

 last h whorl. 



V. excentrica seems to be widely distributed in Great Britain, 

 being represented from different places. 



V. costata: The specimens assigned to this species reported from 

 Iowa, Nebraska, etc., must be referred to the following, the dis- 

 tribution of which in the United States should be further studied. 



V. gracilicosta. There was among the National Museum material 

 over a hundred specimens from drift on the Missouri River, 

 collected near Eort Berthold, Dak. They are all dead shells, yet 

 some of them are in good condition, of 2 - 5-2*8 mm. diam. They, 

 especially the smaller, somewhat resemble V. costata, while the 

 fresh examples of the two lots from Utah mentioned above are 

 decidedly different. As far as I am able to judge from the material 

 seen, the two species are distinct, constantly differing in a number 

 of points. In V. gracilicosta, also averaging larger, the whorls, 

 especially the last, are more depressed above, the aperture is more 

 inclined and oblique, much more curved below than above, and 



