Chap. II] PERIODIC PHENOMENA IN THE TROPICS 255 



in the parts relating to North-west India, the differences of temperature during 

 the seasons of the year are not inconsiderable. But yet during the hot dry season 

 and during the rainy season they are at all events never very great, whereas 

 the difference in the flowering seasons is largely in favour of the hot dry season. 

 In the following table the heading ' Flowering Time ' gives the number of species 

 that were found in flower during the month in question. The small number of 

 flowers during the winter may be due to the low temperature. One and the same 

 species is therefore included in several months, if its flowering period extended 

 over several months: — 



TEMPERATURE, RAINFALL, AND FLOWERING TIME IN 

 NORTH-WEST AND CENTRAL INDIA. 



I have selected from Trimen's Flora of Ceylon species from the lowlands onl}', 

 because reliable meteorological data were available to me only for this region. 

 The island may be divided into two parts, a smaller western and south-western 

 portion with heavy rainfall, and a larger eastern and northern portion with less 

 plentiful rain. More detailed data regarding the climate are given in the 

 accompanying tables : — 



