212 Prof, J. Van der Hoeven on the Succession and 
duce such alterations. Lamarck thinks it very probable that 
fits of anger m Ruminants produce congestions m the forehead, 
and that, by striking each other when they fight, a greater 
secretion of osseous substance and a production of horny matter 
might be provoked, by which means they at last acquired 
horns*. 
It would be difficult to adduce decisive proofs of facts that 
these and similar modifications originate in such manner. The 
advocates of these hypotheses poimt to the very limited time 
wherein it is allowed to man to contemplate the productions of 
the forming power of nature. How different would be our con- 
ception, if we were in the possession of an experience of several 
thousand years! Are these theories illustrated by the remains 
of animals which are imbedded in the many different strata of 
the crust of the earth? ‘This question, at all events, deserves to 
be discussed. 
The fossil remains of organic bodies gave occasion in former 
times to very different opmions. Some believed them to be only 
productions of a sporting Nature—mere /usus nature—remark- 
able representations of plants and animals, but which never were 
true living organisms. Others, not mistaking their true nature, 
believed that all these fossils were the remains of organic beings 
destroyed by a great flood, the deluge recorded in the book of 
Genesis. A further and closer examination of these remains 
proved, more and more, that they could not have belonged to 
the same period, and that there was as great a diversity between 
“those of different strata as between these in general and the now 
living animal and vegetable forms. The fossil vegetable remains 
are chiefly stems, branches, roots, and impressions of leaves of 
plants ; the animal fossils are bones, teeth, scales, or other hard 
external parts, such as shells and polyparia. After the discovery 
of a better distinction between the different formations belong- 
ing to the aqueous rocks (of which distinction the first attempts 
are due to Werner, the man who made straight the way of the 
geologists of our century), the persuasion became more and 
more fixed that in general the oldest and deepest strata contain 
fossils of plants and animals the most different from the now 
living species, and that by degrees the organic forms were modi- 
fied in such a manner that the last-formed strata contain many 
remains of such species as do not differ substantially from those 
of the present time. 
In a short essay on this subject it is impossible to prove this 
statement in detail, but the assertion is the result of all the in- 
vestigations of the paleontologists of this century—Cnuvier, 
Brongniart, Agassiz, and Owen. And the natural corollary of 
* Lamarck, i, p. 256, 
