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SOME MINOR PROBLEMS CONCERNED IN THE LOCAL 



personal knowledge, extending back sixty years. The only variable 

 quantities appear to be the eel and stickleback, and these are easily 

 accounted for. The eel will sometimes leave the water and travel 

 from one pond to another, even across a gravel road. The stickle- 

 back, although not so shown in the table, is the most ubiquitous of 

 all our pond fish ; but it must be remembered that it has often a 

 water communication denied to larger species. It will live in very 

 shallow ditches, which here, for the last half century at least, have 

 been effective barriers against other fish. 



In this brief notice of the aquatic molluscs and the fish, the 

 element of temperature or still water seems to play an important part 

 jn the distribution, for, however well the fish may be capable of 



