Permeability 
149 
resistance of Laminaria disks in solutions of sodium and calcium 
chlorides. While the explanations may be credible they are, for the 
most part, speculative, and on this account they do not call for 
consideration here. It may, however, be said that to regard changes 
in resistance as dependent on, and proportional to, the change in 
quantity of one substance in the cell, appears to the writer, for 
reasons cited in the previous chapter, to neglect the complexity of 
the system involved. 
{To he continued) 
IMPERIAL BOTANICAL CONFERENCE, 1924 
a representative meeting of botanists held recently at the 
Linnean Society's rooms it was decided to hold a Conference of 
British and Overseas botanists early next summer on the occasion 
of the British Empire Exhibition. An Executive Committee was 
appointed with Sir David Brain as Chairman, Dr A. B. Rendle as 
Treasurer, and Mr F. T. Brooks as Hon. Secretary. An invitation 
to attend the Conference has been sent to all Overseas botanists. It 
is expected that the Conference will include discussions upon modem 
aspects of Systematic Botany, Ecology, Morphology, Plant Physio¬ 
logy, Genetics, Plant Pathology, and upon the best means of effecting 
interchanges of students and staff between different parts of the 
Empire. Two meetings of the Executive Committee have now been 
held and the date of the opening of the Conference has been fixed 
for Monday, July y, 1924. The meetings will all be held within 
the week, and excursions will be arranged for the weekend and the 
beginning of the following week. f. t. b. 
