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seems to be rust, Zrichobasis rubigo vera (Lev.). In damp seasons its presence is 
very easily detected on the stems and leaves, especially the latter. It is of a yel- 
lowish red colour, and bursts from under the cuticle where it first forms. It is not. 
of special interest or beauty when magnified. Probably the rust does not materi- 
ally affect the crop. It is followed by Puccinia rubigo vera (De Cand). There is 
another rust which affects the straw of wheat, and is the young state of Puccinia 
graminis (Pers.), but neither this, nor the one which we have just considered, mate- 
rially affects the crop, as they do not appear until the ear of corn is well formed ; 
the mycelium may slightly impair the circulation of the sap, and also damage 
the chlorophyl, but by this time the plant is getting mature. Puccinia graminis 
is found abundantly on the straw late in the season. Its presence is detected by 
black patches more or less elongated, scattered, and bursting through the cuticle 
of the straw. This brand (for such is the English term for the Puccinia) will 
easily be recognized, when highly magnified, by its having the spore divided by a 
septum, and by its pedicel or foot-stalk. Then, as the age of the straw increases, 
you will find other fungi attacking it, if the necessary conditions for their growth 
are present, such as temperature, moisture, and other qualifications. Cladosporiwm 
herbarum (Lk.), the young form of spheria herbarum (Pers.) is to be discovered the 
former with its stalk, on the top of which is the spore, the latter with its beautiful 
sporidia, so yellow and multicellular, numbering generally eight within the ascus. 
Both these forms are very common on wheat, as on many vegetables. You get also 
spheria culmifraga (Fr.), not differimg very much from spheria herbarum, as to 
colour and beauty. Zrysiphe graminis (D.C.), succeeding its young state, which 
in the conidiiforous form is Oidiwm monilioides (Lk.) is to be found in some seasons. 
Also, very rarely, you may meet with the scelerotium of the medicinal Claviceps 
purpurea (Tul.), called in English “ Ergot of Rye.” This scelerotium is really a 
mass of felted mycelium which must for months be kept suitably moist to become 
elaviceps. Then, later on, when the straw is decayed from moisture, you find the 
bristle mould, Chetomium elatum (Kze), with its bristles standing erect, supporting 
the sporidia at their base. These and others all aid in bringing back the straw of 
wheat to the original chemical component parts of which it was formed to the 
parent earth and air again, and so preparing the land once more for the purpose 
to which the Creator asigned it. 
Before closing the subject of the fungi connected with wheat, it will not be 
out of place to allude to the vast importance of a fungus called Saccharomyces 
cerevisie (Meyen) which affects the flour of wheat favourably for mankind, and 
without which it would be impossible to have a good loaf of bread. The ferment- 
ation of dough is caused by the barm acting upon the flour, in consequence of 
which the growth of a Zorula is produced. The more the dough increases iu bulk 
the greater is the increase of the fungus. When sufficiently increased, and the 
dough is put into the oven, the baking process, through the great heat, destroys the 
Saccharomyces, and generates a gas instead, thereby making the loaf light, thus 
proving to us that, although minute fungi are generally considered diseases, the 
so-called diseases may result in great blessings. 
