place of the series of quill-feathers found in the wing of the 
bird. In the second it will be found that this membrane is 
stretched between a series of long and very slender bony rods. 
These are excessively attenuated fingers. And if the hinder 
border of the wing-membrane be traced inwards it will be 
found to be attached to the hind limb. In some species it 
will be found that this membrane passes backwards beyond 
the leg to attach itself to the tail. Here, then, is a wing as 
efficient for its purpose as that of a bird, but constructed on a 
totally different plan. 
Ages ago, before even the birds or the beasts had appeared 
on the earth, the winged dragons, which the Men of Science 
call Pterodactyles, held the proud position of being, not only 
the first, but the only creatures blessed with a backbone that 
could fly. Their wings resembled those of the bats, but 
differed in this, that instead of the wing-membrane being 
stretched between all the fingers, leaving only the thumb 
free, it was attached only to the fifth finger, leaving the 
remaining fingers free, and these were reduced to mere 
vestiges. As with the birds, the breast-bone was very broad 
and was furnished with a keel, while in the bats it takes the 
form of a joined rod, down which no more than a slight keel 
is ever developed. 
But millions of years before the Flying-dragons, birds, 
and bats came into being, the stupendous problem of flight 
144 
