124 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
and in h, f, and ¢ of flowers, while B. empetrifolia predominates in h of 
spines; in all, favouring B. Darwinii as 19 : 13, or 59-3 per cent. 
(28) B. empetrifolia is prepotent in h, f, and ¢ of spines, in h, f, and 
c of leaves, and inhandf of flowers, while B. Darwinii predominates 
in c of flowers ; in all, favouring B. empetrifolia as 20:18, or 60°6 per 
cent. 
(29) B. Darwinii is prepotent in f and ¢ of stems, in h, f, and ¢ of 
spines, and in fof leaves; in all, favouring that ancestor as 18: 12, or 
60 per cent. 
(80) B. Darwinii is prepotent in ¢ of stems, in f and c¢ of spines, 
and in f and ¢ of leaves, while B. empetrifolia predominates in h of 
leaves; in all, favouring B. Darwinii as 17: 138, or 56°6 per cent. 
In addition to the above experiments with Berberis, there are several 
cases on record which tend to show the stability of hybrids in the 
Orchidex, e.g.— 
Paphiopedilum x Harrisianum, a hybrid between P. barbatum (Pfitz) 
and P. villosum (Pfitz), has been raised true from seed when fertilised with 
its own pollen, both by Mr. W. Grey, for Hon. Erastus Corning, Albany, 
U.S.A., and by Mr. R. M. Grey, for Mr. Graves, of Orange, N.Y. 
M. Pauwels, of Boterlaere, France, crossed two distinct varieties of 
this same hybrid, which duly reproduced the specific characters of P. x 
Harrisianum faithfully and well. 
Again, Mr. W. Grey raised P. x vexillarium, a hybrid between P. 
barbatum and P. Fairieanum (Pfitz), from self-fertilised seed. Messrs. 
Veitch, of Chelsea, raised Epidendrum x O’Brienianum, a hybrid between 
K. radicans (Pav.) and E. evectum (Hook. f.), from self-fertilised seed ; 
but one of the seedlings, while retaining the characteristic shape of the 
hybrid, almost reverted 7 colour to its grandparent, KH. evectum. 
This is another illustration of Partial Prepotency, one of the grand- 
parents being prepotent in colour only. 
Dean Herbert—the great pioneer of hybridisation in this country— 
crossed Petunia nyctanigeneflora with P. pheenicea; and the hybrid so 
raised reproduced itself perfectly true from seed, a large batch of seedlings 
being raised. 
Thus the popular idea that hybrids, when self-fertilised, always revert 
to one or other of the ancestral species is evidently not founded on fact. 
Where this is supposed to have been the case it may possibly have 
been due to the hybrid being accidentally fertilised with the pollen of one 
of the ancestral species. 
THe Vicour oF HyBRIDs. 
Most hybrids between distinct species are remarkable for their 
vigorous habit and large size. Many, too, are more profuse and precocious 
in their flowering than their parent species. But the vigour of hybrids 
seems to depend chiefly on their being out-crosses as opposed to being 
inbred. For I observe in my hybrid Berberis that those of the first 
generation, raised by crossing the two wild species, are much more 
vigorous than their parents; but those of the second generation, raised 
from the first hybrid fertilised with its own pollen, are, as a whole, less 
vigorous, being fairly normal in this respect. Yet my hybrid Paphiopedi- 
