148 ILLINOIS STATE ACADEMY OF SCIENCE 



problem of taxonomy has never been put more philosoph- 

 ically than put by him. ' ' 



In doing this work, Lamarck became impressed with 

 the fact that the classification of species and genera was 

 artificial. He, and not a Creator, was determining what 

 constituted species and genera, and what were their 

 limits. He was impressed also with the fact that the 

 distinctions between one species and another were trivial 

 in the extreme, and that intergrades frequently obliter- 

 ated those distinctions. For the purpose of making this 

 matter clear, and for laying a foundation for his new 

 theory, he devotes the first chapter of his book to "Arti- 

 ficial Devices in Dealing with the Productions of Na- 

 ture." After referring to the "artificial aids" of clas- 

 sification, which he says are necessary in dealing with 

 such masses of material, he goes on to say: 



"Nature has made nothing of this kind: and instead 

 of deceiving ourselves into confusing our works with 

 hers,, we should recognize that classes, orders, fam- 

 ilies, genera and nomenclatures are weapons of our 

 own invention. * * * We may rest assured that among 

 her productions nature has not really formed either 

 classes, orders, families, genera or constant species, 

 but only individuals which succeed one another and 

 resemble those from which they sprung." 



From his consideration of these things he got a new 

 idea. That idea was that the "order of nature" was 

 determined by what animals did, and not by what they 

 looked like. He knew that species were not real things 

 in nature, and that animals changed. From what he ob- 

 served he could see that certain changes were brought 

 about by the manner in which animals lived and acted, 

 and not by reason of the existence of any particular en- 

 vironment. Hence, he conceived the idea that animals 

 evolved by the inside forces developed within them by 

 their own actions and efforts, and not by the outside 

 forces of the environment. His theory is condensed into 

 two laws, as follows : 



