i6o 
BRITISH FERNS. 
ever, after their cultivation for several years, the following could 
be found growing wild in suitable places : Scolopendrium vulgare, 
Asplenium Filix-fcemina, Asplenium trichomanes, Nephrodium 
Filix-mas, Nephrodium paleaceum, Nephrodium spinulosum, and 
Aspidium angulare — not normal, but varietal forms, that owed their 
origin to the plants that had been introduced. 
In 1867 I wrote “Our Native Ferns,” and before that time 
began to raise varieties from spores.* In order to economize space, 
spores from the varieties of any one species were sown together ; 
and from the plants so obtained it seemed certain that crosses had 
taken place whilst in the seed-pans. This circumstance caused a 
series of experiments, with a certain object in view, to be com- 
menced. From these experiments it became evident that spores 
gathered from a peculiar part of a frond would produce more strik- 
ing results than from those gathered haphazard. In 1866 the 
late Mr. Clapham had found Asplenium Filix-fcemina, var .proteum, 
and in 1870 he sent me a plant. Spores of this were mixed with 
those of the variety Victoria ?, and produced a series of forms having 
firoteum as the one extreme and V ic tor ice as the other ; every seed- 
ling showing in a greater or less degree the peculiarities of the 
parents. This series was seen in 1879 by Mr. Clapham, who before 
did not believe that ferns could be crossed, but who now became 
convinced ; and on the strength of this conviction he mixed spores 
of Polypodium vulgare, var. Cornubiensc , with the var. bijido- 
cristatum , and raised a crested Cornubiense. 
My next attempt was to cross species ; and spores of Aspidium 
aculeatum were sown with those of Aspidium angulare. The object 
was, to obtain a narrow cruciate variety of Aspidium aculeatum, 
similar to the variety Wakdcyanum of Aspidium angulare, as this 
was as yet a desideratum. Spores of Wakeleyanum were sown 
with those of Aspidium aculeatum, var. densiim; and out of a 
thousand seedlings there were five plants unmistakably Aspidium 
aculeatum, and having cruciate fronds like Wakeleyanum. In 
1884 a short paper, with fronds of this cross, was sent to the Linnman 
Society ; yet even this did not remove the doubt of Botanists; but a 
year later Sir Joseph Hooker informed me that the crossing of 
ferns was an acknowledged fact ; and this change of opinion appears 
to have arisen from seeing a foreign hybrid Adiantum. It is true, 
however, that in 1868 the late Rev. M. J. Berkeley submitted a 
hybrid between Asplenium ebeneum and Scolopendrium rhizophyl- 
lum to the late Sir W. J. Hooker, who replied, it was'the most 
probable instance he had yet met with of a real hybrid amongst 
ferns. In 1888 the late Colonel Jones and myself set forth, in a 
joint paper “On Abnormal Ferns ” t at the British Association 
meeting at Bath, our experience ; Colonel Jones taking Aspidium, 
* At the British Association at Dundee, in 1867, I read a paper on " Hybrid 
Ferns;” but Botanists (except the late Professor Hutton Balfour) would not 
admit they were satisfied that ferns could he hybrids. 
f Printed In the "Annals of Botany,” February, 1889, with illustrations. 
