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THE PROBABLE BACTERIAL ORIGIN OF THE GUM 

 OF LINSEED MUCILAGE. 



{Bacilli LiNi,i.-n., n.spp. ) 



By R. Greig Smith, D.Sc, Macleay Bacteriologist to the 



Society. 



That the production of gum or slime in plants may be due to 

 bacteria, can be readily understood in those cases in which the 

 production is evidently abnormal such as the gummosis of the 

 Sugar-Cane and the gum-flux of certain members of the Legu- 

 minosa3, Rosacese, etc. But when the formation of gum, slime 

 or mucilage is a normal or presumably normal feature of a plant 

 as in Tilia, Linum and the Quince, it is not so easy to believe 

 that the origin may be bacterial. Still, since it has been proved 

 by the author that many of the vegetable gums have a bacterial 

 genesis there is the possibility that the vegetable mucilages, which 

 are after all but varieties of gum, maybe the products of bacteria 

 even when these occur normally in plants. 



I have examined the tissues of the Lime, Quince and Linseed 

 bacteriologically, and in all cases I have found slime-forming 

 bacteria, but as Linseed is perhaps the most important economi- 

 cally, I shall in this paper deal with it. 



It is a matter of common knowledge that the seed of Linum 

 usitatissimum contains practically no starch, and that the 

 digestible carbohydrates consist chiefly of mucilage. Much of 

 the mucilage is found as a layer on the outer surface of the seeds, 

 and when these are soaked in water the mucilage swells but does 

 not to any extent dissolve. It may be removed mechanically 

 and a slime obtained. 

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