On Rust on Cam. Sfc. 467 
minds biassed by the opinions of others, and of course shut their eyes 
to whatever is adverse to such opinions. According to this fancy then, 
the seed from which the Red-Rust springs, is wafted into the corn- 
fields from trees, bushes, and weeds, and hence it is supposed to be 
obvious that much good may be done by destrojang the trees, bushes, 
and weeds, from whence this baneful parasite is propagated and spread. 
The trees usually accused, are the Maple, ^cer campestre; the Ash, 
Frdxinus excelsior; and the Elm, (^Ulmus); — the shrubs, are the 
Barberry, Berberis vulgaris; the Rose, (Rdsd); and the Bramble, 
(Rubus) ; — and the weeds, are the Coltsfoot, Tussilago Farfdra; the 
ljSidi\e& MdiUilQ, Alcliemilla vulgaris ; the Nettle, Urtica dioica ; the 
Groimdsel, Senecio vulgaris; the Dandelion, Leontodon Taraxacum; 
and numerous others. 
Now the veriest tjTO in Crj'ptogamic Botany, knows that the Rtisty 
as it is popularly called, of these plants, is as different in species as 
the plants themselves, and therefore it would be no less rational to 
maintain that a field of wheat would spring up if you should sow bar- 
berries, or coltsfoot seed, than that the seed of the funguses growing 
on these, should produce the corn fungus. Should it be said that it 
is the difference of the nutriment of the fungus which causes the differ- 
ence, I would ask, whether a difference of soil would produce rye or 
oats where wheat seed only had been sown ? 
It may be useful to some of your readers, ^^'ho may have been mis- 
led by books or other authority, into the belief of such absurd fancies, 
to point out a few of the differences of these species of parasite fongns. 
[fig. 73 to 78.] 
These differences in construction, I conceive will be abundantly suf- 
ficient to convince any person not obstinately prejudiced, that the 
Rust in corn, though it may be propagated fi:om the grass in hedges 
and headlands, could not by possibility arise fi-om trees, bushes, colts- 
foot, or other plants, which therefore it would be labour thrown away 
to extirpate with this view. 
I remain, Gentlemen, 
Yours, respectfully, 
Jame.s Renme. 
Lee, Kent, Jan. 14, 1832 
