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XVII. Some further Observations on thff. Nature of the Ergot of Grasses. By 

 Edwin J. Quekett, Esq., F.L.S., fyc. 



Read December 20th, 1842. 



IN the third part of the eighteenth volume of the Transactions of the Linnean 

 Society, are published my observations on the structure of the ergot of grasses, 

 with a view to the discovery of the cause of that formation, which from nume- 

 rous observations was there attributed to the grain becoming infected with a 

 parasitic fungus, the nature of which was also described. It was stated that 

 ' the manner in which this singular production originates (for at present 

 much respecting this part remains uncertain) is, that the sporidia, or more 

 likely the nuclei within them, are by some means introduced into the interior 

 of the grass and ultimately arrive at the grain, which they find the most suit- 

 able matrix for their development ; or they may be brought into contact with 

 the young grain from without, probably by the viscid fluid ; but this is less 

 likely to be the case, as the ergot can be detected before the paleae have opened 

 to admit the fluid." 



Since the publication of the above theory of the production of ergot, expe- 

 riments have been made to carry out the view there stated, and which have 

 succeeded, I imagine, so far as to leave but little doubt as to the true origin of 

 this substance. 



The experiments were as follows. In the beginning of March 1840, twelve 

 healthy grains of -rye, of wheat, and of barley (grown in the neighbourhood of 

 Epsom) were selected and placed in a shallow vessel, which contained a suffi- 

 cient quantity of distilled water to moisten the grains, the whole being covered 

 with a glass shade. In a few days germination commenced in nearly all the 

 grains. At this period an ergot (taken by Prof. Henslow from some wheat 

 grown in Suffolk the preceding year and given me by Dr. Pereira) was placed 

 with the grains ; and the sporidia, which were in abundance on its exterior. 



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