Cuar. XII. SENSITIVENESS OF FILAMENTS. , 291 
masses undergo incessant slow changes of form, uniting 
and again separating; and some of them apparently 
revolve round their own axes. A current of colourless 
granular protoplasm could also be seen travelling 
round the walls of the cells. This current ceases to 
be visible as soon as the contents are well aggregated ; 
but it probably still continues, though no longer 
visible, owing to all the granules in the flowing layer 
having become united with the central masses. “In all 
these respects the filaments of Dionza behave exactly 
like the tentacles of Drosera. 
Notwithstanding this similarity there is one re- 
markable difference. The tentacles of Drosera, after 
their glands have been repeatedly touched, or a particle 
of any kind has been placed on them, become inflected 
and strongly aggregated. No such effect is pro- 
duced by touching the filaments of Dionwa; I com- 
pared, after an hour or two, some which had been 
touched and some which had not, and others after 
twenty-five hours, and there was no difference in the 
contents of the cells. The leaves were kept open all 
the time by clips; so that the filaments were not 
‘pressed against the opposite lobe. 
Drops of water, or a thin broken stream, falling 
from a height on the filaments, did not cause the 
blades to close; though these filaments were afterwards 
proved to be highly sensitive. No doubt, as in the 
case of Drosera, the plant is indifferent to the heaviest 
shower of rain. Drops of a solution of a half an ounce 
of sugar to a fluid ounce of water were repeatedly 
allowed to fall from a height on the filaments, but 
produced no effect, unless they adhered to them. 
Again, I blew many times through a fine pointed 
tube with my utmost force against the filaments 
without any effect; such blowing being received 
