CHAPTER VI. 
PLANTS THAT SHOOT OFF THEIR SPORES OR SEEDS. 
By numerous devices a large number of the lower plants 
send off their ripe spores with considerable force. Some 
call them sling fruits. One 
in particular, Pilobolus cris- 
tallinus, found about damp 
stables, I have observed to 
shoot black masses of spores 
to a spot on a wall six feet 
above the ground, with 
enough force to have carried 
them not less than twelve 
feet. When ripe and dry, 
the spores of most ferns are 
shot from the parent plant 
by a motion forcible enough 
not only to burst the sporan- 
gium , the vessel that con- 
tains the spores, but also to 
turn it inside out. 
35. Dry pods twist as they 
split open and throw the seeds. 
— In December, while ahsen 
Fig. 45. — Spores of Pilobolus before and 
while shooting its spores. 
from home, I collected for 
