189i.] walton mollusca of monroe county. 3 



October 26, 1891. 

 stated meeting. 

 The President, Professor H. L. Fairchild, in the chair. 

 Thirty persons present. 



In the absence of the author, the Secretary read the following 

 paper : 



THE MOLLUSCA OF iMONROE COUNTY, N. Y. 



BY JOHN WALTON. 



The Mollusca form a large group of the Invertebrata and are 

 universally distributed. Anyone therefore, so disposed, may make a 

 collection in his own neighborhood and at almost any season of the 

 year secure specimens for study in regard to their structure and habits. 



Such a pursuit has been my pastime for years and has proved 

 both interesting and instructive. As a result of such pleasant labor 

 I submit the following list of the Mollusca of Monroe County, which 

 embraces, I think, all but a few of the minute species. This list 

 includes 135 species and varieties, representing 30 genera and 14 

 families. Except where otherwise noted, the illustrations have been 

 drawn from living specimens of my own collecting and thoroughly 

 identified. I have made my selection of subjects for illustration 

 mainly because of the uncertainty among students concerning their 

 identity, and the difficulty of obtaining suitably illustrated literature 

 for this purpose ; the many excellent works upon the subjects here 

 under consideration being now out of print. Believing that in sup- 

 plying this lack efficiently a permanent benefit would be rendered to 

 students of our local fauna, I have taken special pains to make these 

 illustrations typical and reliable. For the same reason I have avoided 

 all unnecessary shading, that the proportions and contour of the shell 

 in each case might be the more apparent. 



In preparing this paper I acknowledge my indebtedness to the 

 excellent work of G. W. Binney, " Land and Fresh Water Shells of 

 North America," which I have consulted freely. Nor should I omit 

 to mention De Kay's " Mollusca of New York," with finely colored 

 illustrations ; and the timely aid of the series of Monographs now 

 being published by the Academy of Natural Sciences, Philadelphia, 

 under the general title of " A Manual of Conchology," with Professor 

 H. A. Pilsbury as its able editor ; to all of which works, when prac- 

 ticable, the student is referred for further information concerning the 

 shells of Monroe County. 



