432 WRIGHT : FOLIAR PERIODICITY 
summed up as follows :—The rains fall mainly in the north¬ 
east monsoon, the temperature and humidity are higher 
than at Peradeniya, though the annual rainfall is not half 
so great, and there is one dry hot season from June to 
September. (See plates XXVI. to XXVIII.) 
We have therefore the Colombo climate at sea level, and 
Hakgala at over 5,000 feet, with almost the same climatic 
periodicities as at Peradeniya. At Mannar—sea level—and at 
Badulla over two thousand feet altitude, the climatic periodi¬ 
cities resemble each other, but differ widely from that at 
Peradeniya. In order to make these points still clearer 
I now give a tabulated synopsis taken from the Surveyor- 
General’s report for 1902 :— 
Average Annual Mean Annual Average ai«.,. 
Rainfall. Temperature. Mean Annual - » , 
Inches. Fahrenheit. Humidity. n 
Peradeniya 
82*16 ... 
75*5 
78 
... 1,560 
Hakgala 
91*70 ... 
60*3 
87 
,.. 5.581 
Colombo 
88*15 ... 
80*7 
79 
40 
Mannar 
38-59 ... 
81-8 
82 
12 
Anuradhapura ... 
54*20 ... 
80-2 
78 
295 
Jaffna 
45-47 ... 
82*0 
83 
... — 
Badulla 
76-93 ... 
73*2 
79 
... 2,225 
Peradeniya and Buitenzorg, 
The climate at Buitenzorg differs from that at Peradeniya 
in many ways. At Buitenzorg the rain during 1901 to 1904, 
inclusive, fell on an average of 263 days in each year. 
The humidity of the air in 1904 ranged from 75 in August to 
85 in December, and the average for the years 1901 to 1904, 
inclusive, was 79. The average monthly temperature ranged 
in 1904 from 23*6° to 25*3° C. Though the climate in 
Buitenzorg is more equable than that at Peradeniya it must 
be borne in mind that a definite periodicity does exist, and 
a reference to the curves on plate XXX. will show that the 
rainfall and humidity throughout the year approximate to 
those at Badulla. 
Reference has been made in another part of this paper to 
the marked climatic periodicity prevailing in East Java, and I 
