390 The Fungi. [September, 



is worse than that from putrid fish. When the sound grains are 

 perfectly ripe and dry and assume their light brown color the 

 infected grains also change, but to a somewhat darker brown, retain- 

 ing, however, the same shape which the ovum had at its formation, 

 the rudiments of the stigma also remaining unaltered ! Here we 

 have a minute and no doubt truthful description of the origin, 

 progress and final development of this fungus. 



PROPAGATION OF SMUT. 



It is estimated that the sporules contained in the space of a single 

 grain amount to about four million, and those are easily distinguished 

 and examined through a powerful microscope, and when thus seen 

 have the appearance of articulated globules growing, as before stated, 

 in a bundled manner upon threads. The sporules propagate the 

 smut in the same general way in which seeds propagate phsenoga- 

 mous plants, and are so surpassingly minute as to be scarcely distin- 

 guishable under very high powers of the microscope, appearing thea 

 only like a faint cloud or vapor in a puify escape from the spores. 

 These sporules are so minute that they are readily received into the 

 mouths of the spongelets and conveyed to the seed of the plant, their 

 ultimate position and point of development before described. 



" There is little doubt," says Mr. George W. Johnson, " but that 

 the mode in which smut is imparted to the plant is by its roots im- 

 bibing the extremely minute seeds of the fungus along with the 

 moisture of the soil ; and this opinion is confirmed by the observa- 

 tion that the disease is most prevalent when the winter has been mild 

 and the spring wet, for in such seasons the abundant moisture passing 

 through the soil is most likely to convey the seeds to the mouths of 

 the plant's radical fibres." 



An experiment by Mr. Berkeley, the author of Cryptogamic 

 Botany, goes far to establish the above supposition. He immersed 

 some seeds of wheat in water containing hunt; one of the first ap- 

 pearances was a curious mould, with peculiar spores that sprung upon 

 the spores of bunt. The plants which came up from these seeds were 

 evidently aff"ected, but no communication whatever could be traced 

 between the cells of these plants and the shoots thrown out by the 

 spores. No intrusion whatever of the mycelium developed by the 

 bunt spores into the wheat could be discovered. This shows that the 

 fine contents of the spores do propagate the fungus. It has been 

 often propagated by rubbing seeds before sown with the black powder 

 of the fungus. 



