1876.] 
New Phase of Plant- Life. 
9 
each. The water used must be as absolutely pure as it can 
be made. It is to be especially observed that the experi- 
ments with the weaker solutions ought to be tried after 
several days of very warm weather. Those with the weakest 
solutions should be made on plants which have been kept 
for a considerable time in a warm greenhouse or cool hot- 
house ; but this is by no means necessary for trials with 
solutions of moderate strength.” 
It may, perhaps, allay the scepticism, especially of “ anti- 
Darwinians,” who may read this passage, if they reflect that 
this high sensitiveness of the Drosera is merely in harmony 
with other well-known fadts. Professor Bonders and Dr. 
de Ruyter, of Utrecht, find, from their experiments, that 
less than one-millionth of a grain of sulphate of atropia, in 
an extremely diluted state, if applied diredtly to the iris of a 
dog, paralyses the muscles of this organ. The odorous 
particles which, floating in the air, are detected by 
the olfactory nerves, must be vastly smaller than the 
minutest dose of phosphate of ammonia recognised by the 
Drosera . 
With a view to ascertain the seat and the nature of the 
sensitiveness observed in this remarkable plant, a series of 
careful experiments have been instituted with a variety of 
agents. Some of them produced a poisonous influence, but 
others which have a powerful adiion upon the nervous 
system of animals, produce here no effedt. Hence it is 
concluded that — “ the extreme sensibility of the glands, and 
their power of transmitting an influence to other parts of 
the leaf, causing movement, a modified secretion or 
aggregation does not depend on the presence of a diffused 
element allied to nerve tissue.” This was shown by a 
variety of interesting experiments. The leaves of the 
Drosera were brought in contadt with a variety of narcotics. 
Several of these, “ which adl powerfully upon the nervous 
system of animals, produce no effedt upon Drosera .” We 
may in particular mention the poison of the cobra, so well- 
known for its rapid and deadly adtion upon the nerve- 
centres of animals. But prolonged immersion in this 
poison, far from checking, appears rather to stimulate “ the 
spontaneous movements of the protoplasm in the cells of 
the tentacles.” Hence, then, we have, in this plant, 
sensation and the transmission of impulse not merely 
without demonstrable nerves, but apparently without nerve- 
tissue, and in like manner we have movement without 
muscular fibre ! Concerning the mechanism of these move- 
ments, and the nature of the impulse, our knowledge is still 
VOL. vi. (n.s.) c 
