that the
abrupt changes between the Faunae of the different formations are due
to the lapse of time, of which we have no organic record, during their
"Ante-periods."

The frequent occurrence of strata containing assemblages of organic
forms which are intermediate between those of adjacent formations, is,
to my mind, fatal to this view. In the well-known St. Cassian beds,
for example, Palaeozoic and Mesozoic forms are commingled, and,
between the Cretaceous and the Eocene formations, there are similar
transitional beds. On the other hand, in the middle of the Silurian
series, extensive unconformity of the strata indicates the lapse of
vast intervals of time between the deposit of successive beds, without
any corresponding change in the Fauna.

Professor Haeckel will, I fear, think me unreasonable, if I say that
he seems to be still overshadowed by geological superstitions; and
that he will have to believe in the completeness of the geological
record far less than he does at present. He assumes, for example, that
there was no dry land, nor any terrestrial life, before the end of the
Silurian epoch, simply because, up to the present time, no indications
of fresh water, or terrestrial organisms, have been found in rocks of
older date. And, in speculating upon the origin of a given group, he
rarely goes further back than the "Ante-period," which precedes that
in which the remains of animals belonging to that group are found.
Thus, as fossil remains of the majority of the groups of _Reptilia_
are first found in the Trias, they are assumed to have originated in
the "Antetriassic" period, or between the Permian and Triassic epochs.

I confess this is wholly incredible to me. The Permian and the
Triassic deposits pass completely into one another; there is no sort
of discontinuity answering to an unrecorded "Antetrias;" and, what
is more, we have evidence of immensely extensive dry land during the
formation of these deposits. We know that the dry land of the Trias
absolutely teemed with reptiles of all groups except Pterodactyles,
Snakes, and perhaps Tortoises; there is every probability that true
Birds existed, and _Mammalia_ certainly did. Of the inhabitants of the
Permian dry land, on the contrary, all that have left a record are a
few lizards. Is it conceivable that these last should really
represent the whole terrestrial population of that time, and that
the development of Mammals, of Birds, and of the highest forms of
R