392 TRANSFORMATIONS OF INSECTS. 
slender bodies, long wings, and great legs, which are excessively 
thin and delicate. The Gnats and the Daddy Long Legs are 
the types. 
The natural history of the gnats is full of interest, and even 
the common egnat, Czler pipiens, is well -worthy of study; and 
we may almost wonder at finding such a bloodthirsty and annoy- 
ing being in so delicate and fragile a body. The gnat has a very 
elaborately constructed offensive weapon in its mouth, the struc- 
tures of which, although excessively delicate, can do their perfo- 
rating duty perfectly. All the pieces of the mouth are free, and 
the mandibles are in the shape of sharp blades, toothed on their 
margins. Gnats abound in marshy districts and where there is 
stagnant water, for their larve are aquatic, but cannot live in 
running streams. They are very fond of such places as water 
tubs in gardens, and it does not much matter if the water is not 
quite fresh. 
The male gnats have pretty hairy antennz like little feathers, 
and the females have antenne which are almost plain; it is, there- 
fore, not difficult to distinguish one from the other, and it is rather 
important, for the females are the blood-suckers. When about to 
lay their eggs they seek the water, and, with the assistance of their 
long hind legs, collect and agglutinate them together, and place the 
little boat-shaped mass upon the surface and leave it to its fate. 
The larvze are soon hatched, and grow with great rapidity. They 
swim with great agility, and may be noticed to be constantly as- 
cending and descending, and rushing about in search of prey. The 
transparence of their tissues, the delicacy of the hairs which cover 
them here and there, and the extreme mobility of the segments of 
their bodies, render them very interesting objects for the microscope. 
They are almost always seen with their heads downwards and 
their tails towards the surface of the water. There are two antennze 
on the head, which is also furnished with hairs that direct the food 
towards the mouth. The first segment of the body is large and 
broad, and then the others diminish gradually to the last, which 
carries tufts of hairs, and the last but one is provided with a 
tube, the extremity of which is perforated for a respiratory orifice. 
After the larve have grown to a certain size they undergo a change 
of their skin, and become nymphs, which, although active and 
