322 
OHIO EXPERIMENT STATION: BULLETIN 214 
than the other dust particles carried by the wind. The spores of 
fungi are the means by which these are most commonly reproduced: 
somewhat after the 
7% manner that the 
| higher plants about 
/ us are reproduced 
by their seeds. 
While we have 
cited the bread mold 
eng as a good illustration 
heer to show the struc- 
“=a ~—s« ture of a fungus, it 
6 is not. a parasitic 
-/ fungus; a mold or 
48 like growth which’ 
Fig. 7. 72. A portion of leaf of pea showing breathing pores and 
parasitized by powdery mildew; the horizontal threads (steréle hyphae) 
and summer spore bearing parts of the mildew fungus (fertile hyphae) 
are distinctly shown. In these latter the septa are evident. 74, A 
spore sac (asczs) of the same fungus, 4, 5, 6, show the sucking 
organs (azszoria) of the sterile hypae of this fungus; these penetrate 
the epidermis of the leaf. 10 shows the spores of the rose mildew 
germinating. All highly magnified. (After Tulasne). 
» Note—The stomate in foreground is distorted. See Fig. 2. 
lives upon decaying material is called a sapro- 
phytic fungus. To this same belong the mush- 
rooms or toadstools that may be found in 
manure piles, in the woods and in orchards; the 
fact that we find them in such places shows that © 
there is decaying organic substance at ihat 
point, upon which these plants may subsist. A 
like condition is found in the shelf-fungi on old 
logs and stumps, onthe under surface of which 
we may write our names. Yet if we will usea 
hand lens we may often discover this under 
surface to be but a network filled with small 
openings or pores from which the spores of the 
fungus will in time escape. In like measure the 
spores of mushrooms are found in similar canals 
or upon the sides of the gills beneath the cap of 
this sort of fungus. The bacteria, or fission 
fungi, are one-celled plants multiplying by divi- 
e 
Fig. 8. Fertile hyphae 
‘conidiophores) of the 
downy mildew fungus on 
Cardamine, a mustard pro- 
truding from astomate; the 
one shown in full, bearing 
spores at the end of its 
branches. Highly magni- 
fied. Very similar to this 
are the downy mildews of 
rape, cucumber, lettuce 
and some others. (After 
Zopf). 
sion and by spore production; with bacteria evident mycelium is 
lacking and they are structurally lower in the scale of plant life than 
fungi provided witha mycelium. Bacteria are both parasitic and 
saprophytic. But to return to parasitic fungi: 
. 
