Side by side with the development of the true birds, where wings, of course, were of a totally different type from thave of the flying lizards, other living creatures: were evolving frum much the same sources, though along different lines. These were the mammals, and it wax not long before, here too, the attempt to conquer the air was made, Strangely enough the mammals that have been most suecessful in this enterprise belong to 4 comparatively recently developed group. These are the bats, and they show in many ways a' close Jattinity with the primates, to which great order belong the' monkeys, apes and man himself. But the bats did not evolve a new flight-mechanism. They resuscitated the mechanism used by the fying lizards; that they greatly limbs and fingers: web between the fingers, the limbs and the body, jonly in their case, the fingers were: elongated and not merely the little Thus the four great groups of] flying animals that have occupied the earth from the first signs of fi life down to the present day are (1) the insects, (2) the flying Hizards, (3) the birds, and (4) the bats. "Three of the four great successive waves of living organisms have proved very successful, and only one of them, the flying lizards, has been unable to hold its own and persist to the present day.
But it must not be assumed that the conquest of the air has been confined to there four jereat groups, though it) must be admitted that wey alone show true flight.
Besides them there are a number of creatures that ave to ® greater leswer extent conquered the air and it is of these that I want specially to. speak here, How much these winged lizards could fly it is impossible for us to tell, bur to judge from the great expanse of "some of their wings, shown in their fossil remains, they must have been as proficient many' of our modern birds.
Some of these flying lizards reach-enormous proportions, being larger than the largest of our modern flying birds, with wing spans of from 10 to 15 feet. They mostly had enormous toothed beaks, and when alive must have been fearsome creatures indeed. How they lived, or what they lived on, we cannot' now say, but it is probbable that they were carnivorous and we can imagine the scenes that would occur when a group of these creatures attacked some other of the monsters of rose bygone days,
Text read from the printed page and cleaned; old type leaves the occasional error.