THE WORLD'S FIRST BUTTERFLIES


Thames plants must strike every one as belonging to an ancient order of
life. But the vast clouds of winged _ephemeridae_ that dance over its
waters when there is a rise of "May-fly" in early summer look to be not
only the creatures of a day, but of our day. In the astonishing wave and
rush of life seen at such times, when from every plant and pool winged
creatures are ascending to float in air, it is difficult to picture the
silence and stillness of a world where there were no birds, or hum of
bees, and no signs of the other insects which exceed the other population
of the earth by unnumbered myriads of millions; yet the insects, even the
same identical species which dance over the Thames to-day, are among the
very oldest of living things, just as its plants and its shells are. Rocks
and slate are not ideal butterfly cases; and if the fragile limbs of the
beetle and grasshopper of the successive prehistoric worlds had perished
beyond the power of identification, no one could have felt surprise. But
such has been the industry of modern naturalists--to give the widest name
to those who have devoted their time to the search for, and description
of, fossil insects--that the remains of thousands of species have been
identified, and the time of their appearance upon the earth approximately
fixed. The latest contributor to this elegant branch of the study of
fossils is Mr. Herbert Goss.[1] Perhaps the most interesting of his
conclusions is the antiquity, not only of the existing orders of insects,
but even of their particular families and genera, as compared with
vertebrate animals. It is astonishing to find not only crickets and
beetles existing at periods enormously earlier than the appearance of