133 



lected which present characteristics well worth noticing. Comparison 

 of these varietal forms is, however, deferred until more material shall 

 have been accumulated. 



In conclusion, we would solicit the co-operation of the members of 

 the Club who have not heretofore taken an interest in the study of our 

 shells. So wide and rich a field as here presents itself should be woiked 

 by numerous earnest labourers. Were there more students of this 

 branch of natural science amongst us, vexed questions of variation and 

 distribution might be settled and our present knowledge of the mol- 

 luscan fauna of Canada would certainly be very much increased. 



R E. LATCHFORD. 

 PASCAL POIRIER. 



14th February, 1884. 



Mr. Whiteaves enquired how many species of molluscs were 

 known to exist in this locality. 



Mr. Latchford replied that the Club lists enumerated over 100 

 species, and although it was probable that a critical revision might 

 slightly reduce this number, he thought the reduction would in time be 

 more than made up by species yet unnoticed here, but whose distribution 

 to the south and east left little doubt of their occurrence in this 

 vicinity. 



Mr. Whiteaves stated that there were in North America two 

 distinct types of bivalve ; one eastern, ranging from the Atlantic to the 

 Alleghanies, the other western, from the Mississippi to the Pacific, and 

 that these two types overlapped to some extent. The introduction of 

 the western species was probably due to canals and navigation through 

 the great lakes. He thought that the Anodontas particularly had been 

 unduly increased in nui/iber of species, and that the present tendency 

 was to consider all North American forms as a single species analogous 

 with A. cygnea of Europe. 



Mr. Latchford said that while the number of Anodontas had undoubt- 

 edly been placed too high by the addition of synonyms, he was still far 

 from thinking that our shells could by any possibility be reduced to 

 one species ; and further, that when the unvisited lakes and streams 

 had been examined even a few more miojht be added to our list. 



