OF THE BARBERRY. 327 



in order to ascertain their irritability ; 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 pa- 

 per, and above all, to examine a Barberry- 

 blossom for himself; and if any doubts re- 

 main concerning the existence of vegetable 

 irritability, let him read Senebier'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 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 evident irrita- 

 bility 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 mois- 

 ture causes the, pollen to explode, conse- 



