146 DROSERA ROTUNDIFOLIA. Cuap. VIL 
and another leaf in the same quantity of a solution of one part 
to 3062; in the former case aggregation occurred in 4 m., in the 
latter in 11m. A leaf was then immersed in twenty minims of 
a solution of one part to 4375 of water, so that it received 52, of 
a grain (‘27 mg.); in 5 m. there was a slight change of colour 
in the glands, and in 15 m. small spheres of protoplasm were 
formed in the cells beneath the glands of aii the tentacles. In 
these cases there could not be a shadow of a doubt about the 
action of the solution. 
A solution was then made of one part to 5250 of water, and I 
experimented on fourteen leaves, but will give only a few of the 
cases. Eight young leaves were selected and examined with 
care, and they showed no trace of aggregation. Four of these 
were placed in a drachm (3°549 ml.) of distilled water ; and four 
in a similar vessel, with a drachm of the solution. After a time 
the leaves were examined under a high power, being taken alter- 
nately from the solution and the water. The first leaf was taken 
out of the solution after an immersion of 2 hrs. 40 m., and the 
last leaf out of the water after 3 hrs. 50 m.; the examination 
lasting for 1 hr.40 m. In the four leaves out of the water there 
was no trace of aggregation except in one specimen, in which a 
very few, extremely minute spheres of protoplasm were present 
beneath some of the round glands. All the glands were trans- 
lucent and red. ‘The four leaves which had been immersed in 
the solution, besides being inflected, presented a widely different 
appearance; for the contents of the cells of every single tentacle 
on all four leaves were conspicuously aggregated ; the spheres 
and elongated masses of protoplasm in many cases extending 
halfway down the tentacles. All the glands, both those of the 
central and exterior tentacles. were opaque and blackened; and 
this shows that all had absorbed some of the carbonate. These 
four leaves were of very nearly the same size, and the glands 
were counted on one and found to be 167. This being the case, 
and the four leaves having been immersed in a drachm of the 
solution, each gland could have received on an average only 
gaiss Of a grain (-001009 mg.) of the salt; and this quantity 
sufficed to induce within a short time conspicuous aggregation 
in the cells beneath all the glands. 
A vigorous but rather small red leaf was placed in six 
minims of the same solution (viz. one part to 5250 of water), so 
that it received 53, of a grain (-0675 mg.). In 40 m. the glands. 
appeared rather darker; and in 1 hr. from four to six spheres 
of protoplasm were formed in the cells beneath the glands of 
all the tentacles. I did not count the tentacles, but we maj 
