412 BOTANICAL GAZETTE | DECEMBER 
character, and in a recent letter briefly describes them as “‘scale- 
less fronds of true Ceterach form, but somewhat confluent at the 
tips, and with faced sori in pairs on the lower pinnae, but with single 
asplenioid sori on the upper portions.’”’ In the second case” the evi- 
dence is no less convincing, and the hybridity of the fern may be 
regarded as proven beyond question by anatomical studies, and the 
fact that the cross was several times repeated. In the third case” 
the cross (accomplished by Lowe) was between a cristate angudare and 
a dense form of acu/eatum, resulting in a cruciate aculeatum. As to 
the fertility of these three hybrids: the sporangia of the first, con- 
tained in the fronds sent to Mr. Druery, were immature, so that no 
test of fertility could be made.” In the second case the spores have so 
far proven incapable of germination; but this sterility, Farmer sug- 
gests," may be due to the circumstance of excessive vegetative devel- 
opment, for in the plainer fronds, reverting somewhat to the vu/gare 
type, the spores are much better developed. In the third instance, J 
am informed by Mr. Druery, that, though producing spores freely, the 
plant proved barren in Mr. Lowe’s hands, yet by others it has been 
found fertile, and a few plants have been raised which are freely fertile, 
and have given rise to a number of fine plants now in existence. 
Undoubtedly the parents of the latter hybrid are closely related, and 
a greater fertility might upon this account be expected ; but had it 
proven infertile, as with the Polypodium-Phlebodium cross, it seems 
that even these two negative results might not properly be taken as 
criteria to justify the assumption that fern hybrids are sterile as a 
matter of course. To my mind the supposition of hybridity for A. 
ebenoides is not weakened by the discovery of its evident fertility. I 
am told by Mr. H. J. Webber that in the case of spermatophyte hybrids 
between distinct species the percentage of fertility is very much in 
excess of the common belief; the hundreds of sterile crosses here count 
for nought asan argument leading us to expec? sterility, in the presence 
of an equal host of fertile ones. And so it may be in the case of fern 
hybrids. It appears entirely gratuitous to assume that there can be 
FARMER: Annals of Botany rz : 533 e¢ seg. 1897. 
me rainy Fifty years fern growing. 1896. DRuERyY: Journ. Roy. Hort, So 
24: 292. 
"Mr, Deas states that these fronds are still in his possession, but that the plant 
has probably not surv 
3 FARMER: ; east s of Botany rx: 533 ef seg. 1897. 
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