394 Lecture on the Parasitic Fungi of the British Farm. 



it is not too much to hope that experiments founded on some 

 such results as I have announced from the few I have had leisure 

 to make, may lead to the discovery of a check to the growth of 

 this pestiferous botrytis. 



The root crop of the farm suflers much occasionally from 

 fungal diseases. Parsnips are subject to a variety of the botrytis 

 parasitica, which blights the leaves. The leaves of turnips are 

 attacked by the same fungus ; but a different one, called fusi- 

 sporium, is found on the roots, but with no extensive injury. 

 Mangold- wurzel is affected by the uredo of beet, with brown or 

 black spores like that of the bean ; but in all these cases the con- 

 nexion between the disease of the leaves and decay of the roots 

 has not been sufficiently observed. 



IV. Hops are damaged by an erysiphe, having the habits of that 

 of the pea. It seems to be in its early stage a peculiar mould, 

 but this opinion needs fuller confirmation. The whole subject 

 needs investigation, and I therefore do not dwell upon it. 



V. I now pass from the parasitic fungi of the fields to those 

 found in other parts of the farm, its buildings, yards, and interior 

 economy. The fungi destroying timber are not sufficiently 

 known, though their effects are so common. Dry-rot is gene- 

 rally attributed to the spaicn either of the merulius lacrymans, or 

 weeping morel, so called from the little drops of water it contains, 

 or to that of the polyporus destructor, named from its many pores. 

 But any of the fungi found on wood, and they are numerous, are 

 capable of producing it ; and amongst them are, besides the two 

 mentioned, another morel called vastator, the dcedalea of the oak, 

 deriving its appellation from its labyrinthine structure ; various 

 polypori, thelephora, from ^rfkn, a nipple, by reason of its papillose 

 surface, and sporothricum^ the spores bearing hairy filaments. 

 (See Fig. 16.) The microscopic view of a morsel of sporothricum 



^o°§. 



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Iti. Sporothricum, 



