PRESENT STATE OF ORGANIC ELECTHICITi'. 317 



appears, at the date of the puLlication of his memoirs, to have 

 drawn no more precise condusion from the facts then ob- 

 served ; and states tliat the electrical effects which take place 

 in vegetables are so numerous, that it has only been possible 

 hitherto to observe a limited number of them. 



^I. "Wartmann,* while he admits that the electro-chemical 

 action, which results from the tearing of the textures during 

 the insertion of the electrodes, produces at first a considerable 

 dellection of the needle, states, at the same time, that wlien 

 this action ceases, which it speedily does, there remains a more 

 feeble current, which must be due to the normal electrical 

 action of the parts. He states that vegetable currents pro- 

 bably form closed circuits ; that the extremities of the root- 

 fibres on the one hand, and the tonninations of the leaves on 

 the other, establish a continuity between the ascending peri- 

 pheral and the descending central current ; while the simi- 

 larity in the electrical condition of the exterior of the bark 

 and the interior of the wood probably depends on the medul- 

 lary rays. 



To what Actions and Arrangements in the Plant are its 

 Electrical Disturbances and Currents due ? From what has 

 already been -stated, it must appear that the knowledge 

 hitherto obtained of the relations and circumstances of the 

 electrical disturbances and currents in the plant is not yet 

 sufticiently precise to afford a solution of this question. Be- 

 fore the publication of Du Bois lle}Tuond's researches on the 

 electrical actions of muscle and nerve, and of Pacini on the 

 structure of the batteries in the Toqwdo and Gymnotus, elec- 

 trical excitement in the animal body had not been accurately 

 connected with anatomical structure ; and until a definite 

 electrical current in the plant is distinctly referred to a demon- 

 strable structural arrangement, a precise determination of tlie 

 exciting causes of cuiTcnts in the latter cannot be expected. 



• Bih. Univ. df Om^rr, torn. xv. 



