218 BOTANICAL GAZETTE [SEPTEMBER 
On dry or simply moist media (gelatin, bread, etc.) little or no 
growth can be obtained. In dilute prune juice the fungus grows 
Fic. 2.—Mycelium with sporangia, from moist soil. 
with extreme vigor, form- 
ing a luxuriant mycelium 
of very large, branching, 
continuous filaments 
(fig. 1). Such growths 
are entirely sterile or 
nearly so. Occasionally 
there are produced a few 
large, ovate, terminal 
conidia or sporangia, of 
the phycomycete type, 
which germinate directly 
in water or form swarm- 
spores. Numerous cul- 
tures in various liquid 
media have developed 
nothing but the mycel- 
jum and occasionalspores 
of this kind. This fun- 
gus is nearly sterile under 
such conditions, and en- 
-tirely so on affecte 
lemons in the air, though 
with extreme vegetative 
vigor. Cultures of pieces 
of affected lemon in pure 
water, kept for a long 
time, usually develop 
nothing but mycelium, 
though occasionally 
conidia or sporangia are 
roduced to some extent. 
Bits of this sterile ™Y 
° ce 
celium placed on’ sound lemons in a moist chamber See 
infection and characteristic rot, Lemons soaked in water, 9 
