216 Prof. J. Van der Hoeven on the Succession and 
vation. The succession of new species of plants and animals on 
the surface of the earth seems to be a fact that can hardly be 
denied, although we cannot explain it. If we ascribe no un- 
limited duration to our planet, if we do not believe that it 
existed from eternity, we are compelled also to admit a begin- 
ning of organic bodies—-an origin of life on its surface. How- 
ever impossible it may be to explain the origin of organic bodies, 
the creation of herbs and trees, and of moving, creeping, flying, 
and swimming things, this difficulty of explanation affords no 
reason to deny that there was a beginning. Geological investi- 
gations on strata of rocks and fossil remains of a former animal 
and vegetable world afford proofs that our planet is older than 
sixty centuries ; but they cannot give a demonstration that it 
had no beginning at all*. 
To avoid the difficulty of several consecutive creations, some 
writers have believed that the now living organic bodies origin- 
ated by changes from those species of plants and animals which 
we consider to be extinct. No one, however, so far as I know, 
has given a detailed and accurate account of the manner by which 
the different species which are commonly considered as extinct 
changed into the now living species. Even if their hypothesis 
were admitted, we cannot deny that many forms living in former 
periods have totally disappeared. In the actual condition of the 
animal kingdom on the surface of our globe there are only two 
or three species of Nautilus. It is impossible to think that to 
the production of these the large number of more than a hun- 
dred species of that genus was required—species which succeeded 
each other in the various periods of the history of the earth, 
from the Silurian to the Tertiary strata. Moreover we have 
the much greater number still of other multilocular shells of 
Cephalopods, the Ammonites, which are found in different strata, 
but are wanting in the Tertiary strata as well as in the existing 
order of nature. . 
If we once admit such a mutability of species, we wander into 
the immense field of speculation, where reasoning, or rather 
imagination, must fill up the gaps left by actual observation. 
There is a difficulty in this hypothesis which seems to have been 
commonly overlooked. If we consider the now living species as 
produced by changes from the species of former periods, much 
* It is quite unnecessary to say that, in our day, a literal belief in the 
Bible cannot interfere with the results of astronomical or geological in- 
vestigations. But whatever is stated on the chronology of the acts of 
creation, the investigation must, of course, end in the admission of some 
tirst origin, concerning which science cannot say anything, save the sub- 
lime and simple words of the first verse of the first book of the Bible— 
“In the beginning God created the heavens and the earth.” 
