GEOLOGIC RECONNAISSANCE OF MINDANAO AND SULU. 479 



V. CLIMATE. 



It is difSeiilt to discuss the meteorologie conditions of Mindanao in a 

 general way. The fairly regular and distinctly marked seasons which 

 prevail in Luzon do not seem to obtain in Mindanao. The following 

 table is taken from the monthly reports of the Philij)pine Weather 

 Bureau : 



Rainfall, in millimeters, at Mindanao and Siilu stations durimg 1905. 



Month. 



Zamboanga. 



Isabela. 



Jolo. 



Davao. 



Surigao. 





8.7 



2.6 



0.0 



37.3 



143.8 



25.3 



214. 6 



84.1 



62.6 



13.2 



1.5 



0.0 



9.6 



102.4 



54.0 



140.2 



112.4 



14.=i a 



38.1 

 0.0 



22.4 



0.0 



305.-0 



19.6 

 209.9 



38.9 

 229.6 

 420. 4 



59.4 



69.6 



79.0 

 121.4 

 206.2 



88.4 

 417.8 

 192.8 

 341.4 

 328.3 

 160.6 

 127.3 



66.0 



105.3 

 101.1 

 81.9 

 130.6 

 176.9 

 0.0 

 167.3 

 112.0 

 216.8 

 112.8 

 380.4 

 483.6 



February 





May _ _ 



June 



July 





September 



October 



148.2 ! 320.9 





107.7 

 57.7 



112.3 

 91.2 



December 



Total __ 





892.3 



1,103.0 



1,412.9 



2,129.7 



2,068.7 



A great difference is shown between the rainfall at Zamboanga, at 

 Surigao and at Davao, and the results are very evident in the difference 

 between the forests of these portions of the island. Zamboanga Penin- 

 sula is fairly well forested, if the plain which has been cultivated for a 

 long time is excepted, but the forest of this region is not by any means 

 as luxuriant as that of the Agusan and Davao Valleys. The densest 

 forests in the Philippine Islands, with the possible exception of portions 

 of Mindoro, are probably to be found in the latter districts. 



I was not in the country for a sufficient length of time to render any 

 statement I might make in regard to the healthfulness of various parts 

 of Mindanao of value. The low country in the river valleys and the lake 

 region to the south of the Cotabato is probably not as healthful as the 

 highlands of the Lanao region. Mosquitoes abound in many parts of the 

 former territory and great precautions must be taken against them. The 

 Cotabato Eiver has a particularly bad, but I think underserved, reputa- 

 tion in this respect. I had no fever nor any sickness whatever during the 

 five months I was in Mindanao, but both native and American troops have 

 suffered considerably from malaria. 



A table of the temperatures for the various stations of the island 

 follows : 



