180 ON THE GEOLOGY AND NATURAL HISTORY 
area of country producing in its waters nearly the same life as regards the molluscs, a fact 
highly interesting to the zoologist.” 
To Mr. W. G. Binney were transmitted the land shells, which were examined by him 
with great care. I quote the following remarks from his letter: “These shells are all of 
value, as they form the first contribution to our knowledge of the species found in those 
regions. ‘They are, however, for the most part alluvial. Succinea Haydeni is the only 
perfectly fresh species, the animal being preserved in alcohol. 
“ Helix costata was found in myriads, probably the contribution of many small streams 
above. Of the previously known species it is the most interesting, having been noticed 
previously in few localities and in small numbers. If any argument were needed to establish 
the point of H. minuta (Say), being identical with the European H. pulchella (Mull.), it 
might be found in the fact of the ribbed variety being also found in this country.” 
The following catalogue comprises all the freshwater and land shells known to us on the 
Upper Missouri: 
FLUVIATILE SHELLS. 
1, Unto auatus, Say, Big Sioux river. 
2. Unto LeEvisstsstuus, Lea, cs vc 
3. Unio LuTEoLus, Lam., ‘“ ‘ 
4. Unio Aspertmus, Lea, “ ‘ 
5. Unto rectus, Lea, ‘ “s 
6. Unio ELEGANS, Lea, James river. 
7. Unio ziezac, Lea, White-earth river. 
8. Unio ANADONToIDES, Lea, James river. 
9. MAGARITANA COMPLANATA, Lea, Fort Clark, in Missouri. 
10, ANaponta Ferussactana, Lea, White river, Nebraska. 
11. Lyawea Eopss, Say, Mouth of Big Sioux river. 
12. Lymyga Norrauuiana, Lea, ‘< 66 ‘ 
13. LymNgA HuMitis, Say, ‘ “e ‘“ 
14. Lymnza Haypent, Lea, ‘“ ‘“ “ 
15. Lymyea KirtLanprana, Lea, “ ‘ ‘< 
16. LyMNEA uMBROsA, Say, Grindstone creek, Nebraska Territory. 
17. Lymnea Lusricomwss, Lea, “ beets “ty. te “ 
18. LymygA Puinapenpaica, Lea, «“ é ‘“ “ 
19. PLANORBIS BICARINATUS, Say, Mouth of Big Sioux river. 
20. PLANORBIS TRIVOLVIS, Say, “ “ « 
21. PLanorsis LENTUS, Say, & és « 
22. PLANorRBIS PARVUS, Say, és “ «“ 
