ween these two--none combining in any
degree the characters of the pouter with that of the fantail. Neither
should we ever find such an intermediate form, even had there been
preserved a specimen of every breed of pigeon since the ancestral
rock-pigeon was first tamed by man--a period of probably several
thousand years. We thus see that a complete passage from one very
distinct species to another could not be expected even had we a complete
record of the life of any one period. What we require is a complete
record of all the species that have existed since the two forms began
to diverge from their common ancestor, and this the known imperfection
of the record renders it almost impossible that we should ever attain.
All that we have a right to expect is, that, as we multiply the fossil
forms in any group, the gaps that at first existed in that group shall
become less wide and less numerous; and also that, in some cases, a
tolerably direct series shall be found, by which the more specialised
forms of the present day shall be connected with more generalised
ancestral types. We might also expect that when a country is now
characterised by special groups of animals, the fossil forms that
immediately preceded them shall, for the most part, belong to the same
groups; and further, that, comparing the more ancient with the more
modern types, we should find indications of progression, the earlier
forms being, on the whole, lower in organisation, and less specialised
in structure than the later. Now evidence of evolution of these varied
kinds is what we do find, and almost every fresh discovery adds to their
number and cogency. In order, therefore, to show that the testimony
given by geology is entirely in favour of the theory of descent with
modification, some of the more striking of the facts will now be given.

_Geological Evidences of Evolution._

In an article in _Nature_ (vol. xiv. p. 275), Professor Judd calls
attention to some recent discoveries in the Hungarian plains, of fossil
lacustrine shells, and their careful study by Dr. Neumayr and M. Paul of
the Austrian Geological Survey. The beds in which they occur have
accumulated to the thickness of 2000 feet, containing throughout
abundance of fossils, and divisible into eight zones, each of which
exhibits a well-marked and characteristic fauna. Professor Judd then
describes the bearing of these discoveries as follows--

"The group of shells which affords the most