THINGS TO BE LEARNT. 



I. Leading Facts about Mosquitoes. As everyone 

 knows, mosquitoes invariably spring from larvae which live 

 in stagnant water on the ground or in vessels. But 

 mosquitoes are of very many species, which often differ in 

 their habits. Full information on these points will be found 

 in the literature, of which a list is added to this work. It 

 is necessary to record here only a few leading facts. 



(1) Mosquitoes are the same as gnats. 



(2) All mosquitoes breed in stagnant water. 



(3) The kind commonly known as Culex* carry ele- 

 phantiasis and yellow fever. They breed generally in 

 vessels of water, cisterns, or drains. They bite sometimes 

 in the day and sometimes at night, according to the 

 species. When they are seated upon the wall their tails 

 hang downwards. Their wings are rarely spotted. Their 

 larvae when undisturbed float on the surface of the water 

 head downwards ; when disturbed they wriggle immediately 

 to the bottom of the vessel which contains them. 



(4) The mosquitoes known as Anopheles carry malarial 

 fever. When they are seated on a wall their tails project 

 at an angle outwards. Their larvae are found mostly in 

 shallow puddles on the ground, in small ponds, in slow and 



* A vast number of species of gnats exist, and these species are grouped in a 

 number of genera. Culex and Anopheles are the commonest genera in most 

 places ; but Culex has recently been divided into two genera, Culex and Stego- 

 myia. The latter is the common brindled or tiger mosquito. It carries yellow 

 lever, breeds mostly in vessels of water, and bites much in the daytime. For 

 brevity, I use the word Culex in its old sense. 



