THE DRAWING OF THE SEINE. 163 



character of the chimney does not depend upon the size 

 of the builder, but does have something to do with the lo- 

 cality. Every variation occurs alike, whether along the 

 bank of a ditch, or far out in the meadow, hundreds of 

 yards away. 



These so-called chimneys have attracted universal 

 attention wherever this crayjfish is found, and yet but 

 very little notice has been taten of them by practical 

 naturalists. Girard, some years ago, described the bur- 

 rowing habits of the terrestrial crayfish, making one 

 important statement, to the effect that the chimneys 

 were usually closed with a ball of clay — this closing of 

 the top of the structure being the customary completion 

 of the crayfish's labors. After carefully examining a 

 very large series of these chimneys, mostly when just 

 completed, I have been led to the opposite conclusion — 

 that they are intended to be left open, and become 

 closed by accident, a ball of the clay from the rim of the 

 structure being accidentally misplaced. Now this fact 

 of some chimneys being closed and others open has 

 given rise to a weather-proverb of this character: that 

 when the chimneys are open the weather will be clear, 

 but some hours before the approach of a storm the 

 crayfish plugs up the chimney, to keep the rain out. 



The truth is, the chimneys, as we shall see, are made 

 up of pellets of carefully puddled clay, and the increas- 

 ing moisture of the atmosphere sometimes loosens one 

 or more pellets, on the rim, and they roll inward and 

 get lodged. This simple fact has given rise to a weather- 

 proverb, which in some neighborhoods, all the people 

 swear by. Consider the absurdity of this from another 



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