GIANT BAMBOOS. 
213 
new specific results 4 are to be expected, even in a function 
generally supposed to be so uniform in its progress as the 
rate of growth of an internode. But the result is none 
the less interesting, and may depend at least to some extent 
upon the marked constancy of the conditions other than 
those of moisture. The daily alternation of light and dark¬ 
ness is indeed more intense and the change takes place 
more rapidly in Ceylon than in Europe, and in the case of a 
plant like the giant bamboo it is almost impossible to deter¬ 
mine the exact effect of these changes ; but it seems clear that 
the effect is very small compared to that of changes of moisture. 
Previous Observations upon the growth of bamboos in 
the tropics have not been numerous or elaborate. The best 
known are those of Kraus* in whose paper will be found 
a good summary of earlier observations, which consist 
almost entirely of mere lists of daily measurements. Some 
of the results of my own measurements at Peradeniya differ 
rather widely from those which Kraus obtained at Buitenzorg. 
It will therefore be necessary to give a brief description of 
his experiments. 
Kraus made direct measurements by the aid of a tape 
with which he took the distance between the sharply 
pointed apex of the growing bud and a mark near the base 
of the halm. As the halm grew upwards a Malay was called 
in to hold the upper end of the tape, and still later a pole 
was made use of having a cross piece at the end. Kraus 
states that even towards the close of his observations two 
consecutive measurements, i.e ., made within a few minutes 
of each other, did not differ by more than 2-3 centimetres. 
Hence, although the methods which he used appear some¬ 
what crude, and although there may have been a rather 
greater error in measurements made at intervals of a day, 
it does not appear possible to explain the wide difference 
between Kraus’s results and those described below as being 
due to errors of observation. 
8(10)04 
Ann. Jard. Buitenzorg, XII., p. 196, 1895. 
(ii) 
