226 
LOCK : THE GROWTH OE 
the height of its vegetative growth, and individual culms 
reached a still greater size than those of the first clump* 
These three culms were upon the eastern side of the clumps 
to which they belonged. No. 4 (circumference 59*5 cm.) 
belonged to a third clump on the east side of the pond and 
was on the west side of it* A number of halms on the 
north side of this last clump began to produce flowers about 
September* 
Measurements of No. 1 were started when this culm had 
reached a height of 3*14 metres ; at a height of 18*84 metres 
the upper part of it was broken by the wind and the records 
came to an end. These extend over a period of 55 days, 
from June 20 to August 13. The average rate of growth 
during this period was 286 cm. per day, or 12*5 mm. per hour. 
The greatest growth for any single period of twenty-four 
hours was 46 cm. on July 29-30. 
In the following table (Table IV.) the figures in the first 
column represent the growth in millimetres of this halm 
during the previous 24 hours, as recorded every day at 
7*30 A.M. At the head of the column is given (in Albion 
type) the height at which measurements were begun, and at 
the foot the total height measured is recorded. The readings 
from which the mean temperature during the same period 
were deduced were taken at some distance from the plants, 
and are only approximately correct to half a degree Fahrenheit, 
but they serve to show the very slight variation in this res¬ 
pect. 
The rainfall was recorded in the garden at 9.30 A.M. On 
no occasion, however, did heavy rain fall in the interval 
between 7.30 and 9.30 a.m. 
The remarks in the last column apply in each case to the 
weather during the previous day, i.e ., the first part (7.30 a.m. 
to 5.30 P.M.) of the 24 hours for which the corresponding 
growth is recorded. Growth and rainfall are also represented 
by curves in Fig. 1, PI. XXIII. 
