PRESENT STATE OF ORGANIC ELECTRICITY. 315 



The only obsen-ations in regard to these wliicli have been 

 recorded are l>y Zantedeschi, quoted by Becquerel in liis second 

 memoir.* The Italian obsciTer found tliat at the period of 

 flowering in the tulip, jonquil, and anemone, a deflection of 

 the needle to the extent of 3° or 4°, due to a descending cur- 

 rent, occurs. lie also found in an Azalea, an Amarj'llis, a 

 white lily, and in various species of Opuntia, a cun'cnt passing 

 from the stamen to the pistil ; the one electrode being in 

 contact with the pollen, the other inserted into the stigma. 



Electrical condition of the Fruit. — The only recorded ob- 

 servations on this subject are by Doune,t in a memoir which 

 may be said to have introduced for the first time the subject 

 of vegetable, as well as certain important departments of 

 animal electricity. 



Donne found that when the platinum extremities of the 

 galvanometer wire are plunged into certain fruits, the one at 

 the stalk, the other at the opposite end, the parts exhibit 

 difierent electrical conditions. In the apple and pear a 

 current would appear to pass from the stalk towards the eye 

 at the opposite end; whilst in the peach and apricot the 

 current passes in the contrary tlirection. In the apple and 

 pear the fruit is electro-positive at the distal end, electro- 

 negative at the stallv ; the contrary being the case in the 

 peach and apricot. 



Irrespective of the chemical causes to which these currents 

 are ascribed by Donne and Becquerel, it might be well to 

 determine how far their opposite directions may be referable 

 to morphological differences in the two forms of fruit examined : 

 whether in the monocarpal form, as in the peach, the current 

 be not referable to the centripetal cunent of the leaf ; and 

 whether in the apple form (the fleshy mass of which is not a 



* " Memoire sur les effects ^lectriques, " etc — Menu de V Acad. d< Sciences, 

 torn, xxiii. 



t Ann. dc C/uiil ct de Physique, torn. IviL 



