MICROSCOPIC GARDENING. 



19 



first direct proof of such infection. Here we may compare the 

 method with that where we not only prepare a proper sowing 

 bed, and sow seeds on it which we have reason to believe may 

 germinate and produce a crop, but to make sure that it is really 

 the seeds we have sown which produce the crop, we take up the 

 germinating seeds at intervals and study their growth stage by 

 stage. We are apt to forget the importance of this, and to over- 

 look the fact that if it were necessary to justify our assertion 

 that a grain of wheat gives rise to a wheat-plant when sown, 

 exactly the same rigid procedure would be demanded, and if we 

 remember that prior to 1848 the prothallus of the fern was 

 regarded as its cotyledon, it comes home to us how necessary 

 strict methods are in microscopic gardening, even with relatively 

 large plants. 



De Bary, by the application of his new mode of microscopic 

 gardening, demonstrated two facts — the entrance of the germ- 

 tube of the parasite into the host-plant, and the wonderful 

 phenomenon of Hetercecism — that is to say, a parasite growing 

 in the tissues of one host-plant, such as a grass, develops in 

 one way, but in the tissues of another plant, such as the 

 barberry, it produces quite a different fungus ; and every year 

 since has served to confirm the accuracy of his results. 



Oersted in 1865 showed by a similar method of microscopic 

 gardening that the Gymno sporangium on the juniper, if sown on 

 the leaves of a pear, develops into quite a different fungus called 

 Boestelia, and similar observations have been repeated over and 

 over again by such excellent microscopic gardeners as Mr. 

 Plowright, the late Major Barclay, Mr. Soppit, and others — 

 indeed, we have some reason to be proud of our countrymen as 

 microscopic gardeners in this direction. 



The methods of culture just referred to can evidently be best 

 compared with the sowing of seeds in specially selected or pre- 

 pared beds ; but there is another way of conducting the micro- 

 scopic gardening operations with these parasitic plants, first 

 introduced, I believe, by Robert Hartig in 1878. In cases where 

 a parasitic fungus is growing in the wood of a tree, a piece of the 

 infected wood is cut out by a boring tool, and inserted into the 

 wood of a sound tree ; the fungus here grows, just as does the 

 mycelium of a mushroom when the "spawn" is put into a 

 properly prepared bed. In these cases we may compare the 



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