4o8 NOTES OF A BOTANIST 
that kind of mite is confined to a higher and cooler 
zone, and never descends to the warm zone of the 
Red Bark. 
Let it be observed that these scrobicules, although 
I have no doubt of their origin by insect-agency, are 
quite as good and permanent a botanical character 
as many others — as the sacciferous leaves of Tococa, 
for example. [What a vast length of time, com- 
pared with man's brief life, it must have taken to 
impress a character of permanence on the latter 
character and render it hereditary ! Probably a 
period far longer than those we choose to designate 
"historical" or ''bronze" or "stone." The in- 
imitable researches of Mr. Darwin have rendered it 
(to my mind) almost certain that many of the devia- 
tions from symmetry in the form and direction of 
the parts of a flower have been brought about by 
the direct mechanical agency of insects ; and that 
the origin of every obliquity, unequal-sidedness, and 
so forth, in any organ of a plant, is to be sought in 
the action of forces not only internal, but also 
external to the plant itself.] In this wonderful 
"life," which exists only through perpetual change, 
every equilibrium is unstable, and even what we call 
"permanence" is but a transitory state. 
In fine, the list of structures which I have above 
assigned to Ant-agency might no doubt be very 
much extended, and perhaps more satisfactorily 
classified. I have described only what I have seen 
with my own eyes and noted down on the spot ; and 
corroborative specimens of all the plants mentioned 
exist in the Royal Herbarium at Kew, by means of 
which the accuracy of my account of the structures 
inhabited by ants may at any time be tested. 
