BLAZE-CURRENTS OF VEGETABLE TISSUES. 37 
term of comparison with my land-peas. I call them sea-grapes 
for the present *. 
$7. First Pair of Experiments—The half-ripe pod of a 
"land-pea? (Pisum sativum) is placed symmetrically between 
the electrodes A B, to be submitted to the blazo test. Its 
accidental current is compensated. 
A break induction-shock in the positive direction, from B 
to A, is followed by a blaze-current off-scale in that’ same 
positive direction. 
A break induction-shock in the negative direction, from A 
to B, is followed by a blaze-current off-scale in that same 
negative direction. 
In both cases the blaze-current has been homodrome with the 
exciting current; it has been of quite considerable magnitude, 
‘‘ off-scale " signifying in this case “ greater than 0:02 volt”; it 
was completely abolished after immersion of the pod in hot 
water. 
Deflection. 
0:001 volt through galvanometer .................. sees 40 
0:001 ,, » » -Felectrodes........................ o0 
0:001 ,, » » » +pea-pod ......... 0:9 
0:001 The same after the double blaze .......................- 1:5 
The same after tetanisation .............. esse 1:7 
The same 4 hour later ............ eese 2 
$8. A “ sea-grape ” is placed symmetrically between the same 
pair of electrodes A B, to be submitted to the blaze test. Its 
accidental current is compensated. 
Break induction-shocks in the positive and in the negative 
directions do not arouse any blaze-current. The conductivity of 
the pod is not appreciably altered by the induction-shocks nor 
by strong tetanisation. 
§ 9. Commentary.—This first pair of experiments, which were 
several times repeated with precisely similar results, show in the 
clearest possible manner a remarkable contrast between a land- 
plant and a sea-plant. And obviously the next step will be to 
test other land- and sea-plants for this contrast, and learn 
whether it is justifiable to say that land-plants give blaze- 
currents, but sea-plants do not. 
* Prof. Farmer has informed me since that they were probably Asco- 
phyllum, 
