STATE AGEICULTUBAL SOCIETY. 117 



to short stems or pedicles. The younger ones are ahnost colorless, 

 while the more mature ones are of an orange color. These spores inay, 

 under proper circumstances, grow and give rise to other rust spots. 

 As has been said, tliey take the place of seeds. If the leaf is dissected 

 it will l)e found that under this mass of spores are many fine- fila- 

 ments, ])enetrating the substance of the leaf and drawing upon it for 

 the support of the fungus, as the roots of higher plants draw upon the 

 soil. This root-like mass is called the mycelium. This fungus plant 

 which I have described has received the botanical name of tricho- 

 basis rubigo-vera, the true red rust of the farmers. Later in the season 

 brown spots may appear upon the rusty wheat, either mixed in with 

 the orange-colored ones already described, or at a short distance from 

 them. Tliese also are fungus pustules, which burst and let loose innu- 

 merable spores. But most of the spores difl'er from those of the 

 trichobasis in structure, as well as in color. While those had but a 

 single cell and were spherical or nearly so, these are divided by a parti- 

 tion into two compartments, and are much longer tlian thick. The 

 plant has been long known to science under the name of jmccinia 

 graminis. Puccinia refers to the closeness with which the spores are 

 packed in the pustules ; and graminis simply means of grain. This 

 is the "mildew" of the English farmer. It is no wonder tliat at first 

 '"rust" and "mildew" w^ere supposed to be distinct plants. Latterly, 

 as microscopes have been improved, and botanists have become more 

 skillful in using them, it has been noted that the same pustules some- 

 times contain the simple orange spores of the rust and the double 

 brown cells of the mildew ; and what is more, they spring from the 

 same mycelium. In short, rust and mildew on grain are different 

 forms of one and the same thing. When one of the spores of the 

 mildew lodges in a moist place suitable for its germination, it sends 

 out a number of fine, thread-like tubes, from which arise little stems 

 bearing orange-colored spherical fruits. These fruits in turn fall off 

 m\d set up a growth on their own account. It has been thought pos- 

 sible, though I believe not proved, that still another form of "fruit or 

 spore may be produced, so much smaller that it may enter the circu- 

 lation of the wheat through the roots or the small opening in the 

 leaves called stomata. 



There has been much discussion and surmise as to whether rust 

 and mildew attacked wheat through the leaves or through the roots, 

 but no very definite conclusion has been arrived at. Some have 

 said that the spores entered the leaves through the air pores, or 

 stomata, but it happens that the spores so far known are larger than 

 the pores. As I have hinted, there may be spores not yet observed, 

 so small as to enter these openings. 



From what has been observed in similar plants, it is fair to con- 

 jecture that a spore may germinate on a leaf and send out its thread- 

 like tubes into the stomata, and through these tubes transfer its con- 

 tents to the substance of the leaf, there to give rise to the mycelium 

 or roots which support the perfect plant. This is, however, mere 

 conjecture. Experiments by Prof. Fee indicate a probability that 

 the rusts enter the plants which they attack by way of the roots, 

 thence working their way to the stems and leaves. It is very desira- 

 ble that the matter should be investigated further. If we can decide 

 positively that rust attacks vegetation through the soil, and not 

 through the air, we shall have taken a long step towards deciding 

 whether we can fight it with any hope of success. To know from 



