116 THE WATER CABINET. 
it comes forth “a thing of beauty” to sport in sunbeams, 
and, for but a brief season, lead a life of joy— 
*‘ Fluttering round the jasmine stems, 
Like winged flowers or flying gems.” 
But beauty of the high poetic kind is not the inheritance 
of every member of the class insecta; and the water- 
cabinet presents us with many that have but analogical 
resemblances to the typical structure of the moth or the 
fly, though the naturalist finds beauty in a beetle, and 
points of profound interest in a maggot or grub. 
Since larva are distributed through at least three ele- 
ments, being, according to the species, inhabitants of 
earth, air, and water, the breathing apparatus arrests our 
attention, as constituting a distinct feature in the anatomy 
of the insect. A caterpillar may be regarded as all 
stomach, and the cravings of this immense digesting tube 
easily account for the voracity of larva of all kinds. In 
the larger animals, the food is elaborated into blood, and 
brought to the lungs to be oxygenated by means of 
contact with the air, but the insect does not breathe at 
the mouth, but at the other end, or by means of tubes 
arranged along the sides of the body. In a caterpillar 
there are usually eighteen of these tubes, the orifices of 
which may be seen in action. These tubes all run into 
two larger lateral tubes, or wind-pipes, arranged one on 
each side of the body ; and from these lateral tubes innu- 
merable smaller ones diverge, and convey air to the vessels 
in which the digested food is contained, and thus supply 
it with oxygen. Swammerdam was the first who suc- 
