Illustrations of barnacles, anemones and other invertebrates, 'Balanite Balanus' from the 'Encyclopedie Methodique - Histoire Naturelle les Vers ' published by Pancoucke 1792. Lamarck worked on this encylopedia which included the invertebrates - an area to which he made a permanent contribution to science in describing their taxonomy. He used these accurate figures to refer to as illustration for his important 'Histoire Naturelle des Animaux Sans Vertebres' in 1819. The Balanus barnacles of this plate are a group that Darwin was also to spend many years studying, describing and classifying before his publication of the Origin of Species. Darwin respected Lamarck's invertebrate work, but came to different conclusions on the mode of evolution.