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seed of a minute fungus, whose nature it is to grow on the wheat- 

 straw. Nothing, therefore, is more easy than for the seeds of the 

 fungus to be carried by the wind against the wheat-straw, which is the 

 natural substance from them to grow on. Nothing is easier than for 

 these minute seeds to enter the mouths of the wheat-straw, now widely 

 opened, as if purposely to receive thera. This result, which appears 

 so probable, so much a matter of course, does actually take place. 

 On making a section of a fragment of wheat-straw, cutting it per- 

 pendicularly downwards, you may perceive, by the aid of a micro- 

 scope, the little cavities into which the mouths open ; and in these 

 cavities you will also find the minute seeds of the fungus, just begin- 

 ning to grow. By examining a great number of these little cavities, 

 you will find the fungus in a hundred different states, varying from that 

 of a mere seed to that of perfect plants, clustered together by scores, 

 and squeezing a passage through the mouths into the open air, where 

 they burst, and discharge seed, ripe and ready for further mischief. 

 The shape of a perfect fungus is exactly like that of the unexpanded 

 blossom of a Fuchsia ; and when quite ripe the upper part becomes 

 more globose, splits open, and the seed issues forth. 



In order to make this matter perfectly clear to every comprehen- 

 sion, I have prepared some rather coarse, but certainly characteristic, 

 diagrams of this disease. Fig. 1 represents a portion of blighted 

 wheat-straw, of the natural size. Fig. 2 is a small portion of straw, 



