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on the inside of the stems in such a way that the mycelium of 
the fungus clogs up the water ducts and shuts off the water-supply 
which results in the wilting of the leaves and death of the plants. 
The cotton-plant should also be mentioned in this connection, 
since this plant is attacked by a wilt disease similar in its effects to 
that of the watermelon. And strange to say, this disease is 
caused by a variety of the same fungus which attacks the 
watermelon. 
The best solution of the wilt problem seems to be in the culti- 
vation of resistant varieties of the plants affected. This may 
be done by the selection of natural strains of varieties, by the 
See of hybrids, or by the selection of the seed from the 
stronger plants of any variety. Much progress has been made 
in the cultivation of resistant varieties of cotton. 
Rust oF WHEAT AND OTHER PLANTS. 
It is not HECESsary to inention the importance of wheat as a 
growing is one of the principal industries. As harvest time 
approaches in districts where wheat is relied upon as one of the 
chief farm products the condition of the grain with reference to 
wheat-rust is watched with the greatest of solicitude, for this 
disease has been known to destroy the entire crop. 
Wheat-rust is a very old offender and has been known since 
ancient times. The ancients were very superstitious and believed 
that this disease was caused by evil spirits and the remedy pro- 
posed by them was to frighten away the evil spirits by making a 
loud noise. The cause of wheat-rust is very well known at the 
present time, but the remedy proposed by the ancients is probably 
about as effective as anything which has been suggested in more 
recent times. 
This disease is caused by a fungous parasite and one of the 
most perfect parasites with which we have to deal, and at the 
same time one of the most difficult to control. Three distinct 
stages are represented in the life history of this fungus, the spring 
phase, the summer phase, and the autumnal or winter phase. 
