Development of Animal Organization. 213 



this theorem is that the present speeies of plants and animals 

 are of a more reeent date, that they are not of the same antiquity 

 as plants and animals in general in the history of our planet. 

 If wc suppose that the now living species of organic beings lived 

 already at the same periods to which the remains of older forma- 

 tions belong, then it is perfectly inexplicable why wc do not find 

 the remains of them, or at least of many of them, in all the 

 different strata. If an antiquary finds in some old burial-places 

 only weapons and instruments made of stone or bone, in other 

 sepulchres only bronze implements, he is led naturally to the 

 conclusion that these remains belong to different periods of 

 civilization ; but he would be inconsiderate and devoid of all 

 justification if he admitted that the people in whose sepulchres 

 he had found only stone inif)lements were likewise in the posses- 

 sion of bronze weapons, which he did not find. In the same manner 

 palax)ntological questions are to be discussed. When one of our 

 contemporaries* proposed the opinion that, from the first begin- 

 ning of organization u|)on our planet, all species of plants and 

 animals were created at once, the now living forms as well as 

 the others the remains of which are found in the strata of moun- 

 tains, and that these various strata were formed after the crea- 

 tion of all these species of organic bodies, many of which died 

 out, some in a reuiote, others in a more recent period, — when, I 

 say, one of our contemporaries proposed tliis opinion, no anta- 

 gonist arose, and the paradox passed away hardly remarked. 

 Evidence to the contrary was too strong, and in such a case 

 silence is preferable to the refutation of palpable error. Like 

 silence is also better than demonstration of what is evident of 

 itself. 



It would require nearly a perfect abnegation of all knowledge 

 gathered by observation if we did not admit these two funda- 

 mental results of palaK)ntological investigations, — first, that 

 there existed formerly on our planet other species of plants and 

 animals than those which are now living; and in the second 

 j)lace, that the now living species of plants and animals did not 

 exist from the beginning of life on earth. As to the last thesis, 

 wc are authorized to say with confidence that our now existing 

 species of Mammalia did not live at the same period with the 

 Anoplotheria and Palautheria, the bones of which are dug up in 

 the Tertiary formation of the neighbourhood of Paris. The 

 fishes now swimming in European seas did not swim in the 

 waters whose muddy deposits gave origin to the copper-slate of 

 Maesfeldt, &c. These conclusions are the results of comparative 

 inquiries. If the species now living existed at those periods, 



• Kutorgn, Einige Wortc gepcn die Theorie der stufenweisen Entstehung 

 der urgauisciic WescQ auf dcr Erde. Bonu, 1839, S. 24. 



