112 SPECIES. 



of everything, we are almost entirely ignorant of the conditions 

 necessary to the fecundity of any primitive embryo, excepting 

 certain physical conditions of temperature, liquidity, etc. ; and 

 as, on the other hand, nothing authorises us to believe that 

 the laws existing at the origin of life on our planet have since 

 been abrogated, we see that, if we must necessarily conclude 

 a spontaneous primitive genesis, there is nothing irrational in 

 admitting, until we know farther on the subject, the persistence 

 of the phenomenon. 



Let us return to the subject of species, which, however, we 

 did not quite leave in speaking on the subject of spontaneous 

 generation. Isidore Geoffroy wishes to advance slowly in this 

 matter, and only when facts become patent to all. But he 

 himself has more than once shown, by a noble example, the 

 benefits which science obtains by casting itself beyond the 

 limits of fact, provided that care is taken at first not to give 

 more than a simple hypothetical value to that which we may 

 desire to bring forward. In the question which occupies our 

 attention, we must embrace at one glance the whole animal 

 kingdom since its commencement, in order to deduce the truth 

 of facts which have been observed ; only then these relations, 

 for which science so ardently seeks, would appear in their 

 proper light. On account of this impossibility, we must hope 

 for some more enlightenment, chiefly from geology, and per- 

 haps from experiments. " How many facts would be neces- 

 sary," said Buffon, " in order to pronounce authoritatively, or 

 even to conjecture ? How many experiments are to be tried in 

 order to discover these facts, to acknowledge them, or even to 

 anticipate them by well-founded conjectures ?" 



Two opinions on the origin of species deserve to be noticed, 

 those of Cuvier and Lamarck. This last held Buffon's 

 opinions at the end of his career, and it ought to find in 

 Etienne Geoffroy a defender even more powerful in our eyes 

 than Isidore Geoffroy himself; and especially Darwin, to whom 

 belongs the merit, however, of having propagated, in his 

 popular work, the ideas of Lamarck. 



Cuvier's theory seems to be still the dominant one ; it is sur- 

 rounded by that scholastic prestige which is explained by the 



