LAMARCK THE ZOOLOGIST 



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been discarded many years previous. The great 

 reforms in the classification of shells are evidenced 

 by the numerous manuals of conchology based on 

 the works of Lamarck. 



We used to hear much of the Lamarckian genera 

 of shells, and Lamarck was the first to perceive the 

 necessity of breaking up into smaller categories the 

 few genera of Linn6, which now are regarded as 

 families. He may be said to have had a wonderfully 

 good eye for genera. All his generic divisions were 

 at once accepted, since they were based on valid 

 characters. 



Though not a comparative anatomist, he at once 

 perceived the value of a knowledge of the internal 

 structure of animals, and made effective use of the 

 discoveries of Cuvier and of his predecessors — in 

 fact, basing his system of classification on the 

 organs of respiration, circulation, and the nervous 

 system. 



He intimated that specific characters vary most, 

 and that the peripheral parts of the body, as the 

 shell, outer protective structures, the limbs, mouth- 

 parts, antennae, etc., are first affected by the causes 

 which produce variation, while he distinctly states 

 that it requires a longer time for variations to take 

 place in the internal organs. On the latter he relied 

 in defining his classes. 



One is curious to know how Lamarck viewed the 

 question of species. This is discussed at length by 

 him in his general essays, which are reproduced 

 farther on in this biography, but his definition of 

 what a species is far surpasses in breadth and terse- 



