SYSTEMATIC CATALOGUE OF LAND AND FRESH 



WATER MOLLUSKS OF NORTH AMERICA 



FROM THE REGION NORTH OF THE 



FORTY-NINTH PARALLEL. 



The following annotated catalogue is intended to contain a 

 list of all the species known to inhabit the designated region, 

 with the addition of a few which approach the boundary so closely 

 that it is iiighly probable that on further search their range will 

 be found to cross it. Names of species belonging to the latter 

 category are preceded b)- an asterisk. 



It is intended that the synonymy which follows the name 

 shall exhibit references to the original description of the species, 

 to a good tigure, and to the work in which the synonymy, if at 

 all complicated, may be found most fully set forth. The syn- 

 onymy of some of the genera mentioned seeming to be in great 

 need of elucidation, an attempt has been made to clear it up. 

 In other cases, where the work has elsewhere recently been 

 done, the generic name and authority alone are cited. For the 

 Ilclicidiv and associated forms I have depended upon the ar- 

 rangement of Dr. H. A. Pilsbry, the acknowledged master of 

 the subject; and for the Naiades, in like manner, on the 

 ' Synopsis ' of Mr. Chas. T. Simpson. Some of the other 

 groups I had previously worked up elsewhere, and have utilized 

 the results in this catalogue. 



After the synonymy it has been attempted to state the range 

 of the species geographically, in general terms. This state- 

 ment is followed by a citation of special localities within the 

 designated region from which the species has been reported, and 

 in those cases iil which the writer has verified the report by the 

 examination of specimens, the name of the localit}- is followed 

 by an exclamation mark. 



These data are exemplified or explained by notes following 

 the details of geographical distribution in a separate paragraph. 



The data in many cases have been taken from the literature, 

 a bibliography of which concludes this paper ; and it follows 

 that the resent writer assumes no responsibilitv for the identiti- 



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