194 
James Small. 
THE TRANSLOCATION OF LATEX AND THE 
MULTIPLE RAZOR. 
By James Small, M.Sc. (Lond.), Ph.C., 
Lecturer in Botany , Armstrong College , Durham University. 
[With Six Figures in the Text]. 
1HE present position of our knowledge of the function of latex 
is indicated by Haberlandt (3), who, after devoting several 
pages to the work already done, says, “The preceding discussion 
sufficiently emphasises the need for further experimental research 
upon this subject.” There is an increasing amount of evidence for 
the view that laticiferous tissue forms a distributive system for 
elaborated food-materials, proteids, carbodydrates, etc., and the only 
important objection is made by Kniep (4), who quotes experiments 
by himself and Treub (10), as showing that, if Euphorbia plants 
are kept in the dark for several weeks, the starch grains in the 
latex do not disappear to any appreciable extent. Schimper (7) 
also interpreted his results as disproving the translocation of latex. 
Mangham (5) emphasises the negative evidence of previous 
researches on the translocation of carbohydrates by laticiferous 
tubes and vessels, but it is largely a question of the interpretation of 
results and of an over-emphasis of the behaviour of one constituent 
(the starch grains) of the latex. The presence of proteolytic enzymes 
in the latex of Ficus (2) certainly does not confirm the view that 
latex has no nutritive value. 
Schwendener (8) and Faivre (1) have given somewhat in¬ 
conclusive experiments in support of the translocation of latex, and 
as this is almost a necessary concomitant of the nutritive value, 
the writer has devised an instrument with the aid of which it is 
hoped to solve the problem. 
The latex in the laticiferous vessels is usually, if not always, 
under a certain amount of pressure, with the result that when the 
system is disturbed by a leaf being cut off for examination, the 
condition of the latex in the leaf itself and also in the stem is no 
longer the same. The pressure causes the latex to exude, chiefly 
on the cut surface next the stem. It is necessary, therefore, if the 
condition of the latex in different parts of the leaf is to be studied, 
to have some means of retaining the latex of the leaf in the same 
condition as it is before any cutting has been done. A number of 
workers on translocation have felt the want of an instrument for 
