i6s 

 CONCHOLOGICAL NOTES FROM THE UNITED STATES. 



By LIONEL E. ADAMS, fe.A. 



(Read before the Society, Dec. 14, 1904). 



During last spring and summer I had the opportunity of studying 

 and collecting land and freshwater shells in the Mississippi valley, 

 from St. Louis to New Orleans, and the results were most interesting. 

 The Mississippi and its tributaries are invariably muddy, muddier 

 than the Nile or Euphrates, or indeed than any rivers I have ever 

 seen, the reason being that the great central plain of North America 

 is composed mainly of post-glacial alluvium (the I.oess of the Cham- 

 plain period). In spite of their muddy character, the British collector 

 will be surprised to find that mussels of the Unio viargaritifera class 

 flourish exceedingly, and form a large industry. In the main river 

 and its tributaries are found over four hundred species, some of the 

 thickest-shelled species being used for the manufacture of pearl but- 

 tons, the leading centre of the industry being Muscatine in Iowa. 

 The fishing is conducted chiefly along the Iowa and Illinois shores 

 of the Mississippi, and in the Iowa and Cedar rivers. The mussels 

 are dredged by drag-rakes, often worked by steam winches. In i8g8, 

 1,434 hands were employed in the button factories in Muscatine. 

 In the same year, 3,950 tons of mussels were sold to button manu- 

 facturers, the price averaging £^2 per ton.^ 



Most of the ponds resemble our British ponds in clay districts, 

 seldom clear, but usually unproductive. Some ponds in St. Louis 

 yielded PIa?iorlns trivolvis, which takes the place of our I^l. corneiis; 

 Physa heterostropha, and some Sphceria, resembling our S. palliduvi, 

 which by the way is probably an American importation. 



Land shells are not found by road-sides, or in hedge-banks, which 

 are scarcely ever seen, but must be looked for under logs in woods. 

 I found an abundance of species at the foot of a wooded bluff of 

 limestone, about twenty miles from St. Louis. This spot in flood- 

 time is often fifteen feet under water for a week at a time, yet the 

 shells are always in evidence as soon as the flood has subsided. 

 Rattlesnakes and copperheads infest the bluff, so I was obliged to use 

 a stick to search crevices and turn over loose stones. The monotony 

 of the dead level of the Mississippi valley is relieved by the rising 

 ground on which Vicksburg is situated, undulations on the famous 

 battle-field reaching a height of three hundred or four hundred feet 



I For the above particulars I am indebted to Mr. H. I\I. Smith's "Report on the IMussel 

 Fishery and Pearl Button Industry of the Mississippi River," BtiU. U. S. Fish Cointii., vol. i8, 

 18S9, an abstract of which I am preparing, at the Editor's request, to lay l.iefore the Society. 



