212 Prof. J. Van der Hoeven on the Succession and 



duce such alterations. Lamarck thinks it very probable that 

 fits of anger in Ruminants produce congestions in 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 point 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 opinions. Some believed them to be only 

 productions of a sporting Nature — mere lusus natura — 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 I'ocks (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 palseontologists of this century — Cuvier, 

 Srongniart, Agassiz, and Owen. And the natural corollary of 

 * Lamarck, i. p. 256. 



