OP THE BARBERRY. 249 



filament to be irritable, should express himself as fol- 

 lows : " It has not yet been proved that the movement 

 of the stamens is attended with the contraction of the 

 filaments; which nevertheless was the first proof neces- 

 sary to have been given in order to ascertain their ir- 

 ritability ; it is not even yet well known which is the 

 irritable part of the filaments, and whether it be only 

 their base, as Smith has had the address to discover." 

 In answer to which I need only request any one to 

 read the above account, or the more ample detail in my 

 original paper, and above all, to examine a Barberry- 

 blossom for himself ; and if any doubts remain con- 

 cerning the existence of vegetable irritability, let him 

 read Sennebier's whole chapter intended to disprove 

 it, where that candid philosopher, while he expresses 

 his own doubts, has brought together every thing in 

 its favour. Among the whole of his facts nothing is 



o o 



more decisive than the remarks of Coulomb and Van 

 Marum on the Euphorbia, whose milky juices flow so 

 copiously from a wound, in consequence of the evi- 

 dent irritability of their vessels ; but when the life of 

 the plant is destroyed by electricity, all the flowing is 

 at an end. It is superfluous to add any thing on this 

 subject, and I return to that of the impregnation of 

 flowers. 



I have already mentioned that any moisture causes 

 the pollen to explode, consequently its purpose is 

 liable to be frustrated by rain or heavy dews. Lin- 

 naeus observes that husbandmen find their crops of 



