ON HYBKID1ZATI0N AMONGST VEGETABLES. 



95 



type, the Gladdon, the bulbous race, perhaps the American 

 vernal, the so-called genus Dietes, and some other portions 

 of Iris, to have been departures from the first created type, 

 which occurred in much older times than the more extended 

 diversification of species, and that we shall now find it difficult, 

 if possible, to pass those limits in cross-breeding ; and such is 

 my view of the whole vegetable kingdom, though in some fami- 

 lies it will be found more easy to confound the new forms and 

 revert to ancient associations than in others. In the genus Rosa 

 (though herein I speak from observation and not from experi- 

 ence) there is probably no impediment, not even respecting R. 

 berberifolia, the singular link by which the rose is connected 

 with the Cistus, In Kigidella, on the contrary, it is most difficult 

 to cross the two pendulous species, and I am not sure whether 

 I have at last succeeded in effecting it or not, though the plants 

 are very conformable, except that one flowers in the morning 

 and the other exactly takes its place in the afternoon. The 

 genus Pelargonium, as well as Calceolaria, has furnished much 

 beauty to florists who have crossed ad infinitum the different 

 varieties first obtained by hybridizing. Pelargonium has been 

 subdivided into various genera, which have not been generally 

 adopted, because their limits are obscure and unsatisfactory ; 

 and it is only by trying to cross them that we can find where 

 the positive impediments lie. It is impossible, as far as I have 

 seen, to cross the race to which the horseshoe scarlet belongs, 

 or that to which tricolor belongs, with those which the florist 

 has intermixed. ^Vith very little apparent structural difference, 

 there seems to be a secret insuperable bar ; and I think they 

 were probably severed in a much earlier period of the world 

 than the kinds which will breed together. The first great step 

 for the florist in that race was the production of the plant called 

 Ignescens, by the intermixture of the family, to which betulinum, 

 Citriodorum, &c. belong, with a tuberous-rooted scarlet one, 

 that might however have been thought less likely to breed with 

 them than those which refuse to do so. The fertility of that 

 plant set wide the doors of innovation, but the stream is confined 

 within certain limits. Florists, however, have not availed them- 

 selves of the further help they might have drawn from the 

 colours of the tuberous sorts that might be brought into action, 

 their aim being directed more to size and form than to variety ; 

 but as the scarlet-colour has been drawn from a very small 

 flower to one as large as their rising-sun, so the blood-red of P. 

 sanguineum, as well as the black and the yellow of the tuberous 

 kinds, might probably be brought into like conspicuous mani- 

 festation. 



I am not aware that any difficulty has been found in crossing 



