30 
JOUENAL OF THE ROYAL HOKTICULTURAL SOCIETY. 
A. — Found in company with both parents only, so far as known : 
Cistus florentinus {C. monspeliensis x salvifolius), Cistus ledon {C. mons- 
pessulanus x laurifolius), Cistus longifolius (G. monspessulanus x 
populifolius , Lmaria stricta (Linaria striata x vulgaris), and occurs 
with both parents in West of Europe, Saxifraga luteo -purpurea 
(S. aretioides x calyciflora), Saxifraga amhigua (S. aretioides x calyci- 
flora), Saxifraga ccBsia x mutata, Saxifraga Aizoon x cuneifolia. 
B. — Found in company with one of the parents only. This " often 
happens," Epilohium scaturiginium (E. alsiiKsfolium x palustre), 
Primula brevistyla (P. vulgaris x officinalis) sometimes found without 
either parent, Prunella hybrida [P. laciniata x vidgaris), Linaria stricta 
{Linaria striata x vulgaris). About Montpellier, the last mentioned is 
found only with L. striata. 
C. — Wild hybrids which take the position of species and are esta- 
blished independently of either parent, Betula alpestris (B. alba xnana). 
Entire copses are found in the Jura, Nuphar intermedium (Nuphar 
liiteum X pumilum), BJiododendron intermedium {B. ferruginetim x 
hirsutum), Salvia sylvestris (Salvia nemorosa x pratensis), Primula 
brevistyla (P. vulgaris x. officinalis). 
D. — Hybrids of interest, which for want of information cannot be 
classified as above : Aceras with Orchis, Coeloglossum with Orchis, 
Epipactis speciosa {Epipactis rubiginosa x Cephalanthera alba), 
Equisetum inundatum (E. arvense x limosum), " a rather common 
hybrid," Gymnadenia with Orchis, Himantoglossum with Orchis, 
Nigritella suaveolens (Gymnadenia cojiopsea xNigritella nigra), common 
in the Central Alps, Primula salisburgensis (Primula glutinosa x 
minima). 
One or two questions, I think, are suggested by these hybrids. In 
the first place ought we to question, with a view to alteration, the generic 
or specific position of parents when they produce a fertile hybrid progeny ? 
Montbretia Pottsii and Tritonia aurea (according to the " Kew Index," 
Tritonia Potsii and Crocosmia aurea) have never been regarded, I 
believe, as belonging to the same genus, and yet they produce the very 
fertile progeny Montbretia crocosmicBfiora. Or, to put the same question 
another way, is it possible to use the power of crossing, or the absence of 
it, as any test of generic or specific distinctness ? There does indeed 
appear to be difficulty, because on the one hand plants of very divergent 
character will sometimes cross, while, on the other hand, very similar 
plants will not always do so. If we sort our plants into species and 
varieties according to the highest authority, according to the best evidence 
we know of genetic affinity, and then sort them out according to their 
behaviour in breeding, or not breeding, together, the result is entirely 
different. We might adopt the latter method, but the result would some- 
times be curious. Keally distinct genera ought not, I suppose, to cross at 
all but Cereus and Phyllocactus , Urceolina and Eucharis respectively, 
very distinct genera, according to usual views, do cross. It is interesting, 
however, to make the observation that seedling Phyllocacti are quite 
like young plants of Cereus, and leaves of Urceolina are much like those 
of Eucharis, though in the first case the plant, and in the latter the 
flowers, are enormously different. Among instances of very near allies 
