PROTECTING PLANTS 179 
rusty appearance, due to the development of the spores or 
fruiting bodies. Fig. 211 illustrates the ravages of one of the 
parasitic fungi, the shot- 
hole fungus of the plum. 
Each spot probably rep- 
resents a distinct attack 
of the fungus, and in this 
particular disease these 4h 
injured parts of tissue are Se) "OD 
liable to fall out, leaving 211. Shot-hole disease of plum. 
holes in the leaf. Plum leaves that are attacked early in the sea- 
son by this disease usually drop 
prematurely; but sometimes the 
leaves persist, being riddled by 
holes at the close of the sea- 
son. Fig. 212 is the rust of the 
hollyhock. In this case the 
pustules of the fungus are very 
definite on the under side of the 
leaf. The blisters of leaf-curl 
are shown in Fig. 213. The 
ragged work of apple-scab fungus 
is shown in Fig. 214. 
The constitutional and bacterial diseases usually affect the 
whole plant, or at least large portions of it; and the seat of 
213. Leaf-curl of peach, due to a fungus. 
