24 
THE BOOK OP 
FERN CROSSING AND HYBRIDISING.* 
THE absolutely microscopic nature of the organs which, in 
Ferns, perform the part of flowers renders their systematic 
crossing or hybridising an extremely difficult matter, and, 
humanly speaking, it is impossible to proceed with two Ferns 
with the same certainty of knowledge that the preliminary 
steps are sure and indubitable, as the florist can with two 
distinct flowers. In the one case he deals with something he 
can see and handle : he can take his scissors and remove the 
stamens before the pollen is ripe, and in other ways secure a 
virgin flower on the one hand, while to remove the pollen 
from another set of stamens on another plant is the simplest 
matter imaginable. With both individuals he starts on a clear 
and definite basis, and with ordinary precautions against 
intrusive insects, &c, can practically swear when the seed-pod 
swells that it contains A plus B. With the Fern, however, 
it is quite another matter. Even though we gather a fertile 
frond of a known variety, and isolate it by placing it between 
clean paper in the dwelling-house, the chance of stray spores 
from other Ferns having been shed upon that frond beforehand 
is always existent. Uncertainty No. r. Assuming, however, 
that a pure culture is obtained, the prothalli grow profusely and 
healthily, but when their time for fruition is near we can only 
discern, and that moreover upon their undersides, even with a 
good lens, a number of tiny pimples, some spherical and some 
oblong. A pin’s head would accommodate a dozen of either 
sort. Within the round ones are packed a score or two of 
little tadpole-shaped organisms, only visible under a high- 
powered miscroscope ; and at the bottom of the oblong ones is 
an embryo seed a few degrees bigger. These are the 
elements the Fern crosser has to deal with, and to carry out 
his ideal he should carefully lift one of these tadpole bodies 
just when it bursts its round-headed container and starts on its 
wedding journey across the ocean of a dewdrop, and then 
carefully convey it to another and distant bride selected for it, 
in lieu of the maiden close at hand. Meanwhile it is fairly 
certain that that other bride has many other suitors, and the 
new one may consequently arrive the day after the wedding, 
when, of course, the match-maker is frustrated. He is frustrated, 
but how is he to know it ? To come back to botanical 
phraseology, he may even have isolated the archegonium of 
Paper read at Hybrid Conference of Royal Horticultural Society. 
