254 LAMARCK, HIS LIFE AND WORK 



details and immense nomenclature of the prodigious 

 quantity of animals among which we distinguish an 

 illimitable number of species, " but what is more 

 worthy of you, and of more educational value, you 

 should seek to know the course of nature." " You 

 may enter upon the study of classes, orders, genera, 

 and even of the most interesting species, because this 

 would be useful to you ; but you should never forget 

 that all these subdivisions, which could not, however, 

 be well spared, are artificial, and that nature does not 

 recognize any of them." 



" In the opening lecture of my last year's course I 

 tried to convince you that it is only in the organiza- 

 tion of animals that we find the foundation of the 

 natural relations between the different groups, where 

 they diverge and where they approach each other. 

 Finally, I tried to show you that the enormous series 

 of animals which nature has produced presents, from 

 that of its extremities where are placed the most per- 

 fect animals, down to that which comprises the most 

 imperfect, or the most simple, an evident modifica- 

 tion, though irregularly defined {nuanc^), in the struc- 

 ture of the organization. 



" To-day, after having recalled some of the essen- 

 tial considerations which form the base of this great 

 truth ; after having shown you the principal means 

 by which nature is enabled to create {ppe'rer) her in- 

 numerable productions and to vary them infinitely ; 

 finally, after having made you see that in the use she 

 has made of her power of generating and multiplying 

 living beings she has necessarily proceeded from the 

 more simple to the more complex, gradually compli- 

 cating the organization of these bodies, as also the 

 composition of their substance, while also in that 

 which she has done on non-living bodies she has oc- 



