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ROYAL HORTICULTURAL SOCIETY. 



unfruitful. In this second hybrid it is to be observed that there 

 are three parts of Triticum vulgar e, and in consequence it is nearly 

 accommodated to the vital conditions of T. vulgare. We must 

 remember, however, that it is propagated only artificially. The 

 hybrid has not yet been found wild, and is therefore rare, if it 

 exists at all, and of no great power of endurance. 



So long as hybrids, like stars, were regarded as freaks of nature, 

 they added nothing to our knowledge ; but when it was ascer- 

 tained that the same laws existed in the formation of monsters, 

 though differently directed, they became a fertile source of infor- 

 mation respecting morphology ; and so hybrids, if looked upon as 

 products of a normal fertilization under extraordinary circum- 

 stances, may teach us important lessons respecting the generation 

 of plants. When both parents belong to the same species, we 

 cannot tell what part the male and female parent take respectively 

 in the formation of their progeny. But dissimilar factors are 

 united in hybrids, and an intermediate form is the consequence. 

 The products which arise from reciprocal crossing in plants, un- 

 like those which are formed amongst animals, are perfectly alike. 

 It is of no consequence which is the male and which the female 

 parent. It is therefore a mathematical necessity that the pollen- 

 cells must have just the same part in the act of generation as 

 the ovules. The following observations in the form of aphorisms 

 are to be considered conjectural, and require to be submitted to 

 proof: — 



1. Setting out from the fact that every branch, with a few ex- 

 ceptions, repeats perfectly the type of the plant from which it 

 springs, and that the origin of every branch is referable to the 

 development and division of a single cell, it must be allowed that 

 the cells of plants partake of their specific peculiarities, so that, 

 under favourable circumstances, they can reproduce new indi- 

 viduals. 



2. Embryo-cells and pollen-tubes are cells. They must contain 

 therefore the type of a certain form, which will appear pure and 

 unmixed on the growth of the cells into new branches. 



3. The secret of reproduction depends on the combination of 

 two different cells into a common whole. Accepting this as an 

 axiom, it is natural and necessary in the union of two cells if they 

 belong to differently constituted individuals, that a more or less 

 perfect intermediate form should arise, whose form is not altered, 

 whether a or b supply the pollen ; for each of the two cells, 

 whether embryo-cell or pollen- tube, bears in itself the type of the 



