fore-legs, like those of the bat, or the bird. Rather, it would 
seem, they have developed out of plate-like breathing organs. 
The restful twilight hours of summer tempt not only bats 
from their hiding-places, but a host of other winged creatures 
which are rarely to be seen, or heard, during the glare of noon. 
Among these is the lumbering dor-beetle, who, with lazy 
drone steers clear of solid objects only with difficulty. Many, 
indeed, are his failures. He and his kin are no match for 
bats and owls, who find them juicy morsels! On the next 
opportunity catch one and examine him. His wings are 
curiously interesting. There are the usual two pairs: but 
the fore-wings have been changed to serve as covers for the 
hind-wings. During flight they are spread outwards, and 
indirectly, no doubt, assist flight. But the hind-wings are 
the real propellers. And it will be noticed that when not in 
use they can be folded up in a perfectly wonderful manner, so 
as to lie completely underneath the fore-wings, or “ elytra,” 
so that when the creature is crawling it appears to be wingless. 
Now compare these with the transparent wings of the 
bee, or the gorgeously scale-covered wings of the butterfly. 
It is well worth while. If this examination be done very 
carefully, and with the aid of a magnifying glass, it will be 
found that the fore and hind wings are yoked together in 
the wing of the bee, by a delicate mechanism of hooks. In 
the moths, but not in the butterflies, a bristle, or sometimes 
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