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ROYAL HORTICULTURAL SOCIETY. 



with Camptosorus, The stem, meanwhile, is black as in A. ebeneum ; 

 and what perhaps is of greater importance, there is some differ- 

 ence in the sculpture and transverse section. 



If we take^ into consideration the fact that the genus Campto- 

 sorus cannot finally be separated from Asplenium, that the pinnae 

 partake quite as much of the character of the auricles of the 

 Camptosorus as they do of the piimaB of A. ebeneum, both as regards 

 the ill-developed auricle and the obscure crenulations, that the tip 

 of the frond becomes caudate as in the Camptosorus, while both are 

 proliferous — that though the veins are simple and not reticulate, 

 there is a close resemblance between the fruit — and, above all, 

 when we reflect that only a single plant was found, and that in the 

 company of the two ferns in question, it is very difficult to escape 

 the conclusion that we have here a genuine hybrid. 



I should have been glad to have made a comparison of the 

 spores ; but those in the single imperfect frond communicated 

 were more or less abortive — a circumstance in favour of the hybrid 

 theory. 



It is clear that impregnation can take place only when the pro- 

 embryo is very young, and the antheridia and archegonia are quite 

 fresh, and then only when the spermatozoids have moisture in which 

 they can move about in freedom. Crosses certainly take place be- 

 tween different varieties of Gymnogramma ; or, if the forms with 

 different-coloured meal are regarded as species, we shall have true 

 hybrids. Once, at least, a similar circumstance has taken place 

 amongst the party-coloured species of Pteris. It is, however, 

 strange, if there are really cases of hybridizing, that intermediate 

 forms between distinct species do not occur more frequently in 

 cultivation, where the proembryos are often in a very favourable 

 condition for the access of the spermatozoids of strange species. 

 The subject is one of considerable interest, and by no means un- 

 important, in a practical point of view, to the cultivator. 



It is, however, impossible to make any successful experiments 

 in the hybridizing of ferns, without some definite notions as to the 

 nature of the male and female organs. "Without this any result 

 must be the mere effect of chance. It may not, therefore, be 

 useless, as this ' Journal ' is addressed to horticulturists rather 

 than botanists, to make a few observations on the subject, though 

 they are entirely without novelty. 



Every cultivator knows that the effect of germination in ferns 

 is to produce a little filmy kidney-shaped body, which sends out 

 a frond from the little notch in its margin. Pew, however, in 



