FUNGUSES 65 
of living by themselves, and so is at least one of the 
fungal members, but the association has been formed for 
mutual benefit, reminding one of the joint colonies of 
prairie dogs and owls upon the North American prairies, 
though the lichens have nothing to correspond with the 
rattlesnake, which some have declared to be a third 
amiable partner there. Of course, one would be inclined 
at first to suggest that the fungus was merely a parasite, 
and just lived on the alga, but this is not the case, for 
the alga flourishes exceedingly, and is more prosperous 
than when alone. They live together for generations, 
and actually send out joint colonies. The arrangement 
seems to be that the fungus absorbs water and raw 
material for food, and hands them over to the chlorophyll 
factory of the algal cells, where they are made into 
suitable compounds for the digestion of both parties. 
The fungus is generally outside, and protects the alga 
from the cold and heat and so on, and does its share of 
the joint business quite fairly, in a very different style 
from its pestilent brethren that suck the life out of the 
Potato plant, for instance. 
The same alga may go into partnership with several 
kinds of fungus, and it is generally quite the junior 
partner of the firm. The fungus being outside generally 
seems to have the decision as to the direction of growth 
and so forth. 
As to reproduction, the fungus grows special spore- 
cells, and these are carried off by wind and rain, generally 
to look for a suitable alga, also blown about by wind or 
rain, with which they may join forces. Sometimes, how- 
ever, algal cells are thrown off by the plant at the same 
time, in order that they may be sure of finding partners. 
The plant may depend chiefly on the first way I men- 
F 
