THE ANIMAL KINGDOM. 



113 



beaked humming-bird, they hang motionless before the 

 corolla, plunging their long tongues to the bottom in order 

 to sip the nectar, whilst their wings are agitated by move- 

 ments which the eye cannot follow ! 



The dehcacy of these aerial oars is not less remarkable 

 than their movements. 



However gently we take hold of the wing of a butterfly, 

 our fingers never leave it without having some particles 

 adhering, which seem only a fine dust, the source of the 



58. 1 to 4. Scales from the WiDgs of different Butterflies, seen with the Microscope. 



59. 5. Scale frora Wing of Butterfly, seen with the Magnifyiug-glass. 



magnificent colouring of the insect. But when this dust 

 is submitted to microscopic examination, the observer is 

 surprised to see that each of these grains represents a 

 little flattened plate, lengthened out and of a fine compli- 

 cated structure, which reflects the most magical colours. 

 One of its extremities is generally toothed more or less 

 deeply, whilst the other displays only a little pedicle by 

 which each imperceptible scale is attached to the trans- 

 parent membrane of the wing. 



If a portion of this be now examined by the aid of a 

 low magnifying power, it will be seen that all the scales 



15 



