FERN CROSSING AND HYBRIDIZING 39 
field for combination, as well as our marvellous Polystichums, of 
which the best plumose divisilobes are often sufficiently fertile to 
afford material. Р. setosum especially should be tried with some 
of the best. Could thorough alliances be effected between this lovely 
lucent hard-fronded evergreen Shield Fern and such gems as Prg: 
cristatum (Wollaston No. то), P. а. cristato-gracile, Moly, and some 
of the divisilobe plumosums of Jones and Fox, Pearson and Esplan, 
the results could only be gems of first water. Then there are our 
Osmunda regalis and Osmunda japonica cristata to act as suitors to 
O. cinnamomea, O. interrupta, and O. gracilis, and finally there are 
our lovely forms of Polypodium vulgare, P. v. cristatum, grandiceps, 
Fox, Forster, and Parker, bifido-cristatum, and pulcherrimum, to 
say nothing of P. v. elegantissimum, the British-born parent of Р. 
Schneiderii, all waiting for chances of the introduction which they 
certainly merit to the aristocratic Fern circles of their more stately 
foreign relatives. The field indeed is all but virgin, and we are con- 
fident that careful cultivation of it would yield a host of new and 
charming novelties, provided—always provided—that it be done 
on right lines. 
Into the question of simple crosses between varieties we do not 
propose to enter, space prohibiting, though to us and to British 
Fern specialists generally there is a wide and fertile field still but 
partly cultivated. We have, however, framed our chapter rather 
for the benefit of the more numerous raisers of exotics, who are too 
apt to ignore the merits of our home Ferns altogether, and only here ` 
and there recognize their value in the direction we have endeavoured 
to indicate. i 
In conclusion we may mention that there is one point in connec- 
tion with Fern crossing which has no parallel in flowering plants, 
and that is the possibility of attempts being frustrated by apogamy. 
In numerous Ferns it has been found that the young plants are 
asexually generated in the prothallus, a simple bud arising on the 
spot usually occupied by archegonia. Pteris cretica, Lastrea pseudo- 
mas cristata, Cyrtomium falcatum, and others present this peculiarity 
in nearly every case, and of course under such circumstances no 
crossing is possible, unless in exceptional cases, where the normal 
process may obtain. As Cyrtomium and Lastrea, for instance, are 
closely related, and no crested Cyrtomium had been found, we sowed 
Cyrtomium falcatum and С. fortumett thickly with L. p.-mas cristata, 
obtaining a pure crop of both, a result we should have expected 
had we not forgotten the apogamous character of both members 
of the desired alliance. This, then, constitutes a hidden hindrance 
peculiar to Fern crossing. There are, however, a number of varieties 
of Lastrea p.-mas which afford extremely strong evidence of crossing, 
and we are therefore inclined to believe that apogamy in the species 
is by no means without exceptions, and that normal sexual repro- 
duction frequently occurs. 












