156 



INSECT TRANSFORMATIONS. 



ing water. '* The air, which enters through several 

 openings in the breathing-tube, passes onwards to two 

 lateral wind-pipes, very similar to those of caterpil- 

 lars, as above described. When it wishes to descend 

 to the bottom of the water, it folds up the hairs of the 

 funnel, but by means of its oil retains at their ends a 

 globule of air; and when it wishes to re- ascend, it has 

 only to open its hair funnel again. 



Larva of the common gnat (Culcx Viflitns?) floating in water, 

 greatly magnified, a a, the body and head of the larva. 6, the 

 respiratory apparatus, situated in the tail, c, the larva not mag- 

 nified, 



A similar but more elegant apparatus for the same 

 purpose occurs in the water-grub of a two-winged fly, 

 which Goedart called the chamelion fly ( Straiiomys 

 chamczleon, MEIGEN), because he found it could 

 live nine months without food. The terminal ring of 

 this grub is extended to a considerable length, and 

 fringed at the end with a beautiful star like funnel of 

 thirty feathered hairs. Whether the creature oils these, 



* Biblia, Naturae, i, 154. 



