154 THE VICTORIAK NATURALIST. 



MOSQUITOES. 



By p. H. Anderson. 



(Read before the Field Naturalists^ Club of Victoria, 



%th November, iSSej 



(Continued.) 



The first segment of the abdomen is large and broad ; the 

 others gradually diminish towards the tail, each having on both 

 sides a tuft of hair. The head is flatter than the remainder of 

 the body. The eyes are simple and brownish in colour. Round 

 the mouth are wattles furnished with hair. These move with 

 great rapidity, causing its food, which consists of microscopical 

 animal, vegetable, and earthy matter, to be conveyed to the 

 mouth. 



The transparency of the tissues, the delicacy of the hairs, and 

 the extreme mobility of the segments of the body cause the 

 larva of the mosquito to be a most interesting and general 

 subject for the microscope. The anus is fringed with long 

 hairs, and at the end are four thin, scaly blades, oval and 

 transparent, similar to fins. These are placed in pairs, one 

 projecting from the right and one from the left, and have the 

 power of separating. 



After changing its skin three times in a fortnight the larva 

 then throws off a fourth skin, and is then no longer in the larva 

 state. It is now in the pupa or second stage. On close 

 examination it will be seen it is considerably changed. Its 

 body is shorter and rounder, and the tail is generally bent 

 under the head. This is owing to it being nearly al^j^ays in 

 repose, for in the pupa state it needs no food — its digestive 

 organs are all gone, also the wonderful breathing apparatus of 

 the larva. Two spoon-shaped appendages take the place of 

 the respiratory tube, which it is able to expand and close at the 

 surface of the water, and by this means it breathes. Its 

 motions in the water are slow, and are caused by the bending 

 and straightening of its body. It does not now appear head 

 downwards. Its body is oblong and covered with a transparent 

 skin, and as it gradually developes, the perfect insect is plainly 

 discernible. 



When the time has arrived for the perfect insect to emerge 

 from this stage of metamorphosis the pupa comes to the water's 

 surface, and floats there perfectly at rest, raising the hind part 

 of the body above the water. Before many moments the skin 

 between the breathing trumpets which is now exposed to the 

 sun dries and splits. The opening increases both in length and 

 breadth. As soon as it is sufiiciently large, the imago begins 

 to force its way out of the shell-like case of the pupa. It pro- 

 trudes its head, then its thorax, raising them above the edge of 



