of illuminating connections, and even sees at times
the inevitable sequence of events. Thus if the rise of the Angiospermous
vegetation on the ruins of the Mesozoic world is understood in the light
of geological and climatic changes, and the consequent deploying of
the insects, especially the suctorial insects, is a natural result, the
simultaneous triumph of the birds is not unintelligible. The grains
and fruits of the Angiosperms and the vast swarms of insects provided
immense stores of food; the annihilation of the Pterosaurs left a whole
stratum of the earth free for their occupation.

We saw that a primitive bird, with very striking reptilian features, was
found in the Jurassic rocks, suggesting very clearly the evolution of
the bird from the reptile in the cold of the Permian or Triassic period.
In the Cretaceous we found the birds distributed in a number of genera,
but of two leading types. The Ichthyornis type was a tern-like flying
bird, with socketed teeth and biconcave vertebrae like the reptile, but
otherwise fully evolved into a bird. Its line is believed to survive in
the gannets, cormorants, pelicans, and frigate-birds of to-day. The less
numerous Hesperornis group were large and powerful divers. Then there
is a blank in the record, representing the Cretaceous upheaval, and it
unfortunately conceals the first great ramification of the bird world.
When the light falls again on the Eocene period we find great numbers
of our familiar types quite developed. Primitive types of gulls, herons,
pelicans, quails, ibises, flamingoes, albatrosses, buzzards, hornbills,
falcons, eagles, owls, plovers, and woodcocks are found in the Eocene
beds; the Oligocene beds add parrots, trogons, cranes, marabouts,
secretary-birds, grouse, swallows, and woodpeckers. We cannot suppose
that every type has been preserved, but we see that our bird-world was
virtually created in the early part of the Tertiary Era.

With these more or less familiar types were large ostrich-like survivors
of the older order. In the bed of the sea which covered the site
of London in the Eocene are found the remains of a toothed bird
(Odontopteryx), though the teeth are merely sharp outgrowths of the
edge of the bill. Another bird of the same period and region (Gastornis)
stood about ten feet high, and must have looked something like a wading
ostrich. Other large waders, even more ostrich-like in structure, lived
in North America; and in Patagonia the re