64 DROSERA ROTUNDIFOLIA. Cuar. IN 
ful not to injure the roots; these were washed and placed in a 
little solution of one part of carbonate of ammonia to 146 of 
water. In less than one minute I saw a cloud travelling from 
cell to cell up the roots, with wonderful rapidity. After from 
8m. to 9 m. the fine granules, which caused this cloudy appear- 
ance, became aggregated towards the extremities of the roots 
into quadrangular masses of brown matter; and some of these 
soon changed their forms and became spherical. Some of the 
cells, however, remained unaffected. I repeated the experi- 
ment with another plant of the same species, but before I could 
get the specimen into focus under the microscope, clouds of 
granules and quadrangular masses of reddish and brown 
matter were formed, and had run far up all the roots. A fresh 
root was now left for 18 hrs. in a drachm of a solution of one 
part of the carbonate to 487 of water, so that it received } of 
a grain, or 27024 mg. When examined, the cells of all the 
roots throughout their whole length contained aggregated 
masses of reddish and brown matter. Before making these 
experiments, several roots were closely examined, and not a 
trace of the cloudy appearance or of the granular masses could 
be seen in any of them. Roots were also immersed for 35 m. 
in a solution of one part of carbonate of potash to 218 of water: 
but this salt produced no effect. : 
I may here add that thin slices of the stem of the Euphorbia 
were placed in the same solution, and the cells which were 
green instantly became cloudy, whilst others which were before 
colourless were clouded with brown, owing to the formation of 
numerous granules of this tint. I have also seen with various 
kinds of leaves, left for some time in a solution of carbonate of 
ammonia, that the grains of chlorophyll ran together and 
partially coalesced; and this seems to be a form of aggregation. 
Plants of duck-weed (Lemna) were left for between 30 m. and 
45 m. in a solution of one part of this same salt to 146 of water, 
and three of their roots were then examined. In two of them, 
all the cells which had previously contained only limpid fluid 
now included little green spheres. After from 13 hr. to 2 hrs, 
similar spheres appeared in the cells on the borders of the 
leaves; but whether the ammonia had travelled up the roots or 
had been directly absorbed by the leaves, I cannot say. As one 
species, Lemna arrhiza, produces no roots, the latter alternative 
is perhaps the most probable. After about 23 hrs. some of the 
little green spheres in the roots were broken up into small 
granules which exhibited Brownian movements. Some duck. 
weed was also left for 1 hr. 30 m. in a solution of one part of 
