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situated on the thorax. They remain near the surface of the 

 water and wriggle up and down by a quick movement of their tails, 

 whereby they shoot backwards in the same style as do the cray fish. 

 Their existence is in this stage limited to a week and on a fine still 

 moi'iiing the skin bursts at the back and the mosquito is liberated 

 from the pupa. We see first of all six long black legs working 

 themselves out, and immediately afterwards a slim delicate body 

 follows them, taking up a position on the top of the old skin, 

 which hitherto shut it oft" from the world. Here it remains for a 

 while until the v/ings are dry, but should an unexpected gust of 

 wind come, the frail craft is capsized and our mosquito is drowned 

 in the element, in which it spent the early part of its life. As 

 soon as the wings are dry the female mosquito says good-bye to the 

 water and comes into our houses to give us a serenade with her 

 delightful soprano voice and also to make a meal at our expense. 

 Only the fertilized females return to the water to deposit their 

 eggs, after which they die, having accomplished the end of their 

 existence. — Such is the life of a mosquito and any one who wants 

 to observe it for himself has only to take a tumbler full of water 

 f.'om some cistern or the other and carefully watch it day 

 by day. Only the females bite, the males living in re- 

 tirement in the woods, near their birth-place. — A female 

 mosquito lays about 300 eggs and when you take into 

 consideration that in four weeks these eggs produce mosquitoes 

 capable of laying the same number of eggs, you can well imagine 

 how it is we are visited at times by such swarms of mosquitoes. 



After having thus heard something of the zoological 

 character and life histoiy of the mosquitoes we now come to the 

 economic part of the paper, but first of all I would like to be 

 distinctly understood that the following suggestions only apply to 

 towns. We shall nov/ look at 



THE CAUSES WHICH TEND TO INCREASE THE NUMBER OF MOSQUITOES 



IN TOWN. 



When the rainy season sets in, and after showers have fallen 

 for some time, little pools of stagnant water are formed all over the 

 country and about the larger gardens of Port-of-Spain, and as you 

 have seen above, these are exactly the conditions mosquitoes require 

 for their existence. A few fine days between the rainy ones is 

 also very conducive to the development of a great number of 

 adult mosquitoes, as these must necessarily have fine weather to 

 escape from the pupa shell. The cesspits about the town, which 

 during the rainy season, fill with water are also good breeding 

 places, the rain water tanks, anti-formicas, and all vessels filled 

 with stagnant water, regardless of size, ax'e also made use of by 

 mosquitoes to deposit their eggs in. It is remai'kable what a 



