192 TILLEKS OF THE GKOUND CHAP. 



does not afford some refreshment of this kind, to 

 restore the moisture that has been exhausted by 

 the heats of the previous day." 



We know now that Sir Joseph was wrong in 

 thinking that the use of the pores on the leaves of 

 plants is to allow them to take in water. It is the 

 roots which take in water, and the leaf-pores allow 

 the surplus to escape, besides having other uses. 

 He was, however, perfectly right in believing that it 

 was through these pores that the fungus found an 

 entrance. Here is his account of the process, which 

 is rather interesting : 



" By these pores, which exist also on the leaves 

 and glumes [that is, the scales on the ears], it is 

 presumed that the seeds of the fungus gain ad- 

 mission, and at the bottom of the hollows to which 

 they lead, they germinate and push their minute 

 roots, no doubt (though these have not yet been 

 traced), into the cellular tissue beyond the bark, 

 where they draw their nourishment, by intercept- 

 ing the sap that was intended by nature for the 

 nutriment of the grain ; the corn, of course, becomes 

 shrivelled in proportion as the fungi are more or 

 less numerous on the plant ; and as the kernel only 

 is abstracted from the grain, while the cortical part 

 remains undiminished, the proportion of flour to 

 bran in blighted corn is always reduced in the same 

 degree as the corn is made light. Some corn of this 



