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C. J. Cornish - The Naturalist on the Thames
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 birds or fish, but that they conformed in type to the
families in which they are classed to-day. Though they become fewer and fewer as they are tracked back
up the river of time, there are not found in the earliest fossil-bearing rocks any connecting links or earlier
and simpler forms of insect life, or a clue to the common ancestor of insects, spiders, and shrimps, which
naturalists would dearly like to discover. There is a baffling completeness about these creatures. When in
the lias period, for instance, the vertebrates were huge saurian reptiles and flying lizards, and scarcely
any of our existing classes of fish had come into existence, the beetles, cockroaches, crickets, and white
ants were there, with all the distinguishing characteristics of the existing families as they were settled by
Linnaeus.
The first insect known to have existed, a creature of such vast antiquity that it deserves all the respect
which the parvenu man can summon and offer to it, was - a cockroach. This, the father of all
black-beetles, probably walked the earth in solitary magnificence when not only kitchens, but even
kitchen-middens were undreamt of, possibly millions of years before Neolithic man had even a back cave
to offer with the remains of last night's supper for the cockroach of the period to enjoy. His discovery
established the fact that in the Silurian period there were insects, though, as the only piece of his remains
found was a wing, there has been room for dispute as to the exact species. Mr. Goss in his preface to the
second edition of his book notes that what is probably a still older insect has been found in the lower
Silurian in Sweden. This was not a cockroach, but apparently something worse. If the Latin name,
Protocimex Silurius, be literally translated, it means the original Silurian bug. It was a fair conjecture
that insects appeared about the same time as land plants first grew on the earth. As almost all the species
either feed on some vegetable substances in growth or decay, or else live upon other insects, some such
provision of food was necessary for them. Remains of such plants were discovered in the Silurian rocks.
In the Devonian formations, which contain the next oldest set of fossil insects, numbers of conifers and
ferns are found. Yet even then the only vertebrate animals seem to have been fish. The insects still had
the land all to themselves. Of one of these Devonian insects the base of a wing was the only part
preserved in the rock. From this it was possible to tell the order to which the creature belonged. It was
one of the Neuroptera - insects with wings in which the veins run straight down the wing,
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