the Rocky Mountains. Few or no snails will be found in waters polluted 

 by sewage or manufacturing wastes. A safe admonition to the amateur 

 snail hunter, however, is to look everywhere for snails where there is water. 

 Even wet meadows and the damp shores of ponds and rivers may harbor 

 forms of the small lymnaeids called Fossaria. Fresh water limpets (Ferrissia, 

 etc.) may often be found in dead clam shells or on rocks. 



How to Collect the Snails. Collecting fresh water snails is usually a 

 simple process much more easily accomplished than collecting insects, 

 especially butterflies. They do not fly away and are easily approached for 

 capture. Thanks to one of our oldest members, Dr. Bryant Walker, now 

 gone from among us, who lived in Detroit, Michigan, a useful dipper was 

 invented which is fittingly called a Walker dipper or dredge. It is so 

 efficient that usually no other implement is necessary. This dipper is about 

 6 inches in diameter at the top and 5 inches in diameter at the bottom, 

 with a depth of about 3 inches. The bottom is covered with copper wire 

 screening of a sufficiently large mesh to allow the mud and water to run 

 through and retain the shells. It is fastened to a handle 5 or 6 feet in 

 length. A broom handle often makes a good handle. The dipper should 

 be made of copper to prevent rusting. If copper is not available then the 

 sides of the dipper may be made of tinned iron and the bottom may be of 

 copper. A dipper of this kind has been in use by the v^iter for several years 

 and shows no indication of wearing out. I feel sure that the museum of the 

 University of Michigan would be willing to furnish specifications for this 

 dredge or dipper and it could be made by any good tinsmith. 



With this very efficient collecting apparatus there is little difficulty in 

 sweeping any body of water for possible snails. It may be used on the shore 

 of lakes and ponds, to explore mud holes and small streams or sweep the 

 bottom of a lake in water down to 6 feet in depth. It is excellent for 

 sweeping through vegetation in a lake or river, the snails falling into the 

 dipper from which they are easily picked out. For collecting snails in large 

 areas of vegetation in lakes or ponds, as in the pond weeds (Potamogeton) , 

 it is best to pull up some of the vegetation and place this in a large pail. 

 Washing and shaking this vegetation in the pail will dislodge the snails and 

 often several hundred will be found in the bottom of the pail after this 

 process. Pond lily leaves, and also the stems of sedges (Typha, Scirpus, etc.) 

 should be carefully examined for small snails, especially the little fresh 

 water limpets, Ferrissia. Many larger snails, as Physa, lymnaeids, and small 

 planorbids, as well as Amnicola, may also be found on lily leaves. Most 

 lake collecting should be done from a row boat. In some localities the 

 vegetation may be pulled to shore with a rake. 



Such large snails as Campeloma and Viviparus may be found by run- 

 ning the hand through the mud and sand bordering the shores of lakes 

 and rivers where they live, often in large numbers. The Walker dipper is 

 also useful in such places. From rocks on shores of rivers and lakes the 

 snails may be picked by hand. This is especially true of Goniohasis, Pleuro- 

 ccra, Somatogyrus, and other snails found in our mid- western streams. 



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