The Sporing of the Fern 257 
of the prothallus is expended in nourishing the 
oospore. Sometimes it so happens that several 
sister oospores are ready to grow at the same 
time. But generally in this case one dominates 
the rest in the great struggle for life, and draws 
into itself all the nutriment which the prothallus 
can bestow. And so a prothallus seldom gives 
rise to more than one little fern. 
If a prothallus is insufficiently nourished it may 
bear antheridia only, and no archegionia at all. 
Such ‘‘ male’’ prothalli are apt to develop after an 
eccentric fashion of their own. They are often long 
and narrow, sometimes almost filamentous in form 
and grow into irregular projections. In fact, they 
are sometimes ‘‘ all bubukles, whelks, and knobs,’’ 
like Bardolph’s countenance. 
They are relatively small, and may even be 
reduced to a single vegetative cell, an antheridium, 
and a few root-hairs. 
Several common native ferns, notably the great 
Osmundas, always give origin to a number of starve- 
ling ‘‘ male’’ prothalli, in addition to the larger and 
more symmetrical ones which bear both antheridia 
and archegonia. 
And in a few flowerless aquatic plants, closely 
akin to ferns, all the prothalli are either male or 
