156 JAS. J. SIMPSON — ENTOMOLOGICAL 



entirely to the savannah forest ; and G.fusca to the tropical rain forest regions. 

 More detailed information of the distribution of these species will, however, be 

 given in the general narrative, but enough has been said to show the bearing of 

 the nature of the vegetation on the subject in hand. 



II. Climate and Rainfall. 



The Colony of Sierra Leone is small and compact, and at no point is it much 

 over 200 miles from the sea. Consequently, one would not expect to find very 

 great differences in the various parts. It must be remembered also that the 

 meteorological data are very scanty and have not been kept in any regular 

 manner over a definite period. After considerable difficulty I have, however, 

 collected such data as are available, and have arranged them in tables so as to 

 bring out the major features. Only for the year 1911 have I been able to get 

 anything like complete information, but as no attempt has been made, prior to 

 this, to tabulate systematically the data available, it is hoped that this grouping 

 may serve as a basis for future work. The writer is fully aware that further 

 information may modify some of the conclusions arrived at, but it is improbable 

 that any radical changes will be necessary. 



There are two distinct seasons in Sierra Leone, known respectively as the 

 " wet " and the " dry." The former is generally spoken of as the " rains." It 

 commences in May and lasts until about October, the commencement and 

 close of the rainy season being heralded by tornados — violent thunderstorms 

 accompanied by strong winds. The minimum humidity occurs at the end of 

 March or the beginning of April, when the moisture is absorbed by the dry 

 harmattan which blows intermittently from December to March. The harmattan 

 is a very hot, dry wind which comes from the north-east, carrying with it fine 

 impalpable dust from the Sahara. 



The temperature, on the whole, varies little from day to day, the daily range, 

 as well as the average daily temperature, being least in the middle of the rains, 

 the period maximum of humidity. 



Before one proceeds to tabulate and analyse the available meteorological data, 

 it might be well to point out the locations of the various places where these were 

 taken. 



(1.) Freetown — the exact locality of this station is described on p. 153. 

 (2.) Bonthe is also situated on the coast, on Sherbro Island (see p. 180). 

 (3.) Bo is a large station on the railway, 136 miles from Freetown, and about 



60 miles from the coast (see p. 171). 

 (4.) Daru h also on the railway, where it crosses the Moa River, 213 miles 



from Freetown, and less than 100 miles from the coast (see p. 172). 

 (5.) Batkanu is situated on the Rokell River, about 60 miles from the coast ; 



it is the headquarters of the Karene District. 

 (6.) Kaballa is in the north-east of the Proctectorate, and is the most 



northerly station in Sierra Leone ; it is the headquarters of the 



Koinadugu District ; the country around is mountainous. 



