Chap. III. PERIOD OF CUVIER. 197 



that of Anaimn and Emima of Aristotle. The three leading groups designated 

 under the name of Apathetic, Sensitive, and Intelligent aninial.s, are an imitation 

 of the four branches of Cuvier; but, far from resting upon such a definite idea 

 as the divisions of Cuvier, which involve a special plan of structure, they are 

 founded upon the assumption that the psychical faculties of animals present a serial 

 gradation, which, when applied as a principle of classification, is certainly not admis- 

 sible. To say that neither Infusoria, iior Polypi, nor Kadiata, nor Tunicata, nor 

 Worms feel, is certainly a very erroneous assertion. They manifest sensations quite 

 as distinctly as many of the animals included in the second type which are called 

 Sensitive. And as to the other assertion, that they move only by their excited 

 irritability, we need only watch the Starfishes to be satisfied that their motions 

 are determined by internal impulses and not by external excitation. Modern inves- 

 tigations have shown that most of them have a nervous system, and many even 

 organs of senses. 



The Sensitive animals are distinguished from the third tj-pe, the Intelligent 

 animals, by the character of their sensations. It is stated, in respect to the Sensi- 

 tive animals, that they obtain from their sensations only perceptions of objects, a 

 sort of simple ideas which they are unable to combine so as to derive from 

 them complex ones, while the Intelligent animals are said to obtain ideas which 

 they may preserve, and to perform with them operations by which they arrive 

 at new ideas. They are said to be Intelligent. Even now, fifty years after 

 Lamarck made those assertions, I doubt whether it is possible to distinguish in 

 that way between the sensations of the Fishes, for instance, and those of the 

 Cephalopods. It is true, the structure of the animals called Sensitive and Intelli- 

 gent by Lamarck diflers greatly, but a large number of his Sensitive animals are 

 constructed upon the same plan as many of those he includes among the Apathetic ; 

 they embrace, moreover, two diflierent {jlans of structure, and animal psychology 

 is certainly not so far advanceij as to aftbrd the least foundation for the distinc- 

 tions here introduced. 



Even from his own point of view, his arrangement of the classes is less perfect 

 than he might have made it, as the Annelids stand nearer to the Worms than 

 the Insects, and are very inferior to them. Having fiiiled to perceive the value 

 of the idea of })lan, and having substituted for it that of a more or less com- 

 plicated structure, Lamarck unites among his Apathetic animals, Radiates (the Polypi 

 and Radiaria) with MoUusks, (the Tunicata,) and with Articulates (the Worms.) 

 Among the Sensitive animals, he unites Articulates (the InsectvS, Arachnids, Crus- 

 tacea, Annelids, and Cinipcds) with Mollusks (the Conchifcra, and the Mollusks 

 proper.) Among tiie lutfUigeiit animals, ho includes the ancient four classes of 

 Vertebrates, the Fishes, Reptiles, Birds, and Mammalia. 



