STUDY OF MOSQUITO LARViE. 53 



appeared very suitable, no mosquito larv?e could be found in tbem; though I 

 caught several female mosquitoes full of eggs in the fringe of bush round the 

 swamp. The absence of larvre may have l)een due to the activity of small 

 silvery-spotted fish inhabiting the pools. The introduction of these small 

 fish into the large water-holes, if successful, might diminish the num})er of 

 mosquito larvae ; but probably the conditions in the large holes are un- 

 favourable to the small fish, or they would long ago have occupied them 

 naturally. 



Borrow-pits exist along the course of the railway. During the rains they 

 all contain water, during the dry season many of them become dry. Large 

 numbers of larvae were found in these pits. 



Puddles are produced by the flooding of unlevel roads. Such collections 

 of water are favourable for the growth of larvae, and when the water is 

 opaque Anopheline larvae are almost always found. 



Bamboos grow in clumps at the water-holes or in the bush beyond the 

 villages. When cut, the stumps become filled with water during the rains, 

 and if in a shady position retain water for long periods. In this water 

 mosquito larvae are often found. The bamboo should be cut through with 

 a small saw below the internal disc and the contents examined in a suitable 

 dish. 



Fetich-pots are found at the entrances to most native villages. They are 

 usually damaged native cooking-pots made of unglazed earthenware They 

 are placed upon a mound at the entrance to a village, and contain v/ater, 

 vegetable debris and usually cowrie shells, and are often under the shade of 

 trees. Mosquito larva? are frequently found in their contents. 



The rainy season usually begins in May and lasts till November. The 

 temperature varies between 80° F. to 90° F. in the shade in the daytime, but 

 falls lower at nieht in the middle of the rains. 



BULL. ENT. RES. VOL. I. PART I. APRIL 1 9 10. 



