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THE BUTTERFLY. 
tiles in a roof. Sometimes the plume will be 
divided at the tip into a number of little teeth, 
and then again it will be quite plain, without 
any division at all. The shape also is very 
various, even on the same wing. As, for 
instance, on one part the plumes will be oval; 
on another there will be a cluster of three- 
cornered plumes, and then a group that are 
heart-shaped; and here and there taller ones 
grow up amongst the rest, and overtop them. 
The clusters of plumes are quite different 
from each other in color, and form the pattern 
of clouds and bars and spots, that give the 
wing all its beauty. In some cases the plumes 
so completely stud the wing, that nothing else 
is to be seen; but in others, they leave 
spaces, where the transparent membrane shines 
through, and these spaces look like so many 
windows. 
The butterfly has, as you know, two pairs of 
wings, and when she is at rest, she holds them 
upright. The hinder wings of the swallow-tailed 
butterfly* are each prolonged into a tail, and 
this gives her a very bird-like appearance. Such 
an appendage to the wing is rare in England, 
but in the tropics it is very common indeed. 
The tail will be of a great length, and there 
* Papilio machaon. 
