MEMOIR OF LAMARCK. 49 



rials into the bed of the sea ; and the latter, from 

 continual efforts to deepen its bottom, necessarily 

 throws them out on one side or other. Hence there 

 results a general movement and a constant trans- 

 portation of the ocean, which has perhaps already 

 made several circuits of the globe. This shifting 

 cannot occur without displacing the centre of gravity 

 in the globe ; a circumstance which would have the 

 effect of displacing the axis itself, and changing the 

 temperature of the different climates. — In order to 

 silence any doubts that may arise in the minds of 

 his readers from not observing these changes going 

 forward, Lamarck is careful to add, as in the case 

 of the supposed transformation of species, that an 

 unlimited length of time must be allowed for their 

 accomplishment. 



But the work on which Lamarck's fame is prin- 

 cipally founded, and which has conferred a most 

 important service on zoology, is his Histoire Naturelle 

 des Animaux sans Vertebres. From the time of its 

 appearance, this work has ever been regarded as 

 one of the highest authority, and has formed the 

 principal regulator of most departments of this ex- 

 tensive race of animals. The work extends to seven 

 octavo volumes, and is entitled " Natural History 

 of invertebrate Animals, presenting the general 

 and particular Characters of these Animals, their 

 Distribution, Classes, Families, Genera, and the 

 principal Species referable thereto." The first vo- 

 lume is entirely occupied with an introduction, the 

 object of which is to determine the essential cha- 



VOL. xxxi. D 



