72 MODE OF ACTION. 



This uredo was very carefully examined by 

 M. Bauer, and his .drawings of the various 

 points of interest in which it should be viewed 

 are made with his accustomed skill. He has not, 

 however, shown the mycelium as it is shown 

 here. Opinions seem in favour of the entrance 

 of this fungus by the spongioles of the roots, 

 and of their being propelled through the tis- 

 sues by the ascending sap, as was stated in the 

 case of the uredo segetum. This question will 

 be discussed presently. It is when it enters 

 the young ovum that it finds a suitable place 

 for vegetating. When once there, all fecunda- 

 tion is destroyed by it ; there is no develop- 

 ment of the parts of fructification, and no 

 embryo whatever can be detected. Still the 

 grain swells on ; and when the harvest is cut, 

 the diseased grains are actually larger in cir- 

 cumference than those which are sound. Be- 

 fore they assume their final brown hue, tlie 

 diseased grains are of a very dark green coloui*, 

 and emit, when broken, the peculiar fetid smell 

 previously mentioned. Singularly enough, tlie 

 stigmata of the flowers are not destroyed. 



M. Bauer's remarks on the progress of this 

 fungus are well deserving of a place in every 

 treatise upon it. He says, " The earliest 



