Chapter XI. 



Blights, Black Fungi and Root-fungi* 



Blights. There remains to be considered a large group of 

 sac-fungi, which from the color of their fruit-bodies are classed 

 together under the name of black fungi. Very good examples 

 of the black fungi are furnished by the blights which occur on 

 the leaves of the higher plants. As a type, may be selected the 

 lilac-blight, which in autumn forms a white scurf on lilac leaves. 

 This scurf is the vegetative body of the blight and consists of 

 a cobwebby mass of delicate, white, branching filaments, some 

 of which penetrate the tissues of the leaf, while others spread 

 themselves over its surface. If one, in the autumn, looks closely 

 at a blighted lilac leaf it will be discovered that there are pres- 

 ent on its surface a great number of tiny black specks which by 

 the naked eye can be seen to have a spherical shape. These are 

 the fruit-bodies of the blight. Within the black skin of each, 

 sacs are formed, much as in the truffle, and in the sacs spores 

 are produced. The fruits of the blights are many of them re- 

 markable for their development of peculiar anchor-like append- 

 ages which grow out from the surface. In the lilac-blight 

 these appendages are branched in a regular fashion forming at 

 the ends a series of curved prongs. The willow-blight, on wil- 

 low leaves, has the ends of its fruit-appendages hooked and such 

 blights are called hooked blights. The blights common on 

 grass leaves in autumn and causing portions of the turf to look 

 as if a little whitewash had been spilled upon it are supplied 

 with fruit-appendages which are not hooked or branched at the 

 end. In another sort of blight the appendages are sharply 

 pointed like thorns. 



Toadstool-blight. A few of the so-called black fungi belie 

 their name, for instead of black, their color is rather yellowish 



