276 LAMARCK, HIS LIFE AND WORK 



IV. Lamarck's Views as published in 1806.* 



" Those who have observed much and have 

 consulted the great collections, have been able to 

 convince themselves that as gradually as the cir- 

 cumstances of their habitat, of exposure to their 

 surroundings, of climate, food, mode of living, etc., 

 have changed, the characters of size, form, of propor- 

 tion between the parts, of color, of consistence, of 

 duration, of agility, and of industry have propor- 

 tionately changed. 



" They have been able to see, as regards the 

 animals, that the more frequent and longer sustained 

 use of any organ gradually strengthens this organ, 

 develops it, enlarges it, and gives it a power propor- 

 tional to the length of time it has been used ; while 

 the constant lack of use of such an organ insensibly 

 weakens it, causes it to deteriorate, progressively 

 diminishes its faculties, and tends to make it waste 

 away.t 



" Finally, it has been remarked that all that nature 

 has made individuals to acquire or lose by the sus- 

 tained influence of circumstances where their race 

 has existed for a long time, she has preserved by 

 heredity in the new individuals which have originated 

 from them {elle le conserve par la generation aux nou- 

 veaux individus qui en provienneni). These verities 

 are firmly grounded, and can only be misunderstood 



'•'' Discours d^ Ouveriure dtc Cours des Aniviaux sans Vertlbres, 

 prononc^ dans le Museum d'Hisioire naiurelle en mai 1806. (No 

 imprint, 8°, pp. 108.) Only the most important passages are here 

 translated. 



f " We know that all the forms of organs compared to the uses of 

 these same organs are always perfectly adapted. But there is a 

 common error in this connection, since it is thought that the forms 

 of organs have caused their functions {en ont amen^ Vemploi), whereas 

 it is easy to demonstrate by observation that it is the uses (usages) 

 which have given origin to the forms of organs." 



