Notes . 
289 
but this latter translocation only occurs when the partial starvation 
of the cell has rendered possible the dissolution of starch by enzyme- 
action. 
From the invert- sugar, derived from the cane-sugar, the dextrose 
is more readily used up for the respiratory processes, and possibly also 
for new tissue-building, than is the levulose : hence in a given time 
more levulose than dextrose must pass out of the leaf into the stem. 
Knowing as we do how enormous is the resistance which living 
protoplasm affords to the ordinary physical processes of diffusion, 
it seems highly improbable that the wandering of the sugars in 
living plant-tissue is altogether dependent upon osmosis. It is no 
doubt to the continuity of the protoplasm from cell to cell, which 
may now be regarded as an established fact, that we must look 
for a full explanation of those rapid translocations of certain sub- 
stances which we know take place. That diffusibility is however 
a determining factor of importance cannot, we think, be doubted 
when we regard the nature of the substances which up to the present 
time have been recognized as wandering metabolites. 
THE GENUS THEMATOCAKPUS. — With reference to my 
note on this genus in ‘Annals of Botany/ vol. vi, no. 21, April, 1892, 
a letter has been received from Dr. Zahlbruckner, of which the fol- 
lowing is a translation. 
‘ In the “ Annalen des k. k. naturhist. Hofmuseums in Wien,” 
vol. vi, I described my genus Trematocarpus , basing it on Lobelia 
macrostachys , Hook, et Arn., which differs absolutely from all species 
of Lobelia in the structure of its fruit. Mr. W. B. Hemsley raised 
objections, in the ‘Annals of Botany’ of April, 1892, to my proposed 
new genus on the ground either that the genus Trematocarpus does 
not refer to Lobelia macrostachys , Hook, et Arn. ; or — and this seems 
to be regarded by Mr. Hemsley as more probable — that the capsules 
in my possession were not normal, but had been eaten by insects. As 
to the latter objection, I can only state that the capsules on which my 
description is based are quite normal, and that my description is an 
accurate account of the facts. Were the holes in the wall of the 
capsule due to insects, the margins of the holes would consist merely 
of the tissue of the wall, or possibly there might have been some 
development of cork from callus. But this is not the case. On the 
contrary, the holes are bounded by a raised ring consisting of fibrous 
