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THE AMEBIC AN NATURALIST [Vol. XLVIII 



Oliver's work on the natural history of plants. Accord- 

 ing to this view, responses are advantageous and for the 

 purpose of preserving the plant. Thus response and 

 adaptation become synonymous (Coulter, '08), a usage 

 quite inapplicable to animal structure. At the beginning 

 of the recognition of the response phenomena of corals 

 Wood-Jones takes essentially the view of adaptation 

 which botanists have tried and rejected. 



Lamarck, who was for many years engaged in botanical 

 work, must have noted many cases of advantageous 

 structural response in plants. Later he undertook the 

 study of invertebrates which show great plasticity, and 

 was naturally much influenced in the development of his 

 theory of transmutation of species by the response phe- 

 nomena in the plastic organisms which he studied. Thus 

 the responses of motile (as well as sessile) organisms 

 which result from their own activities or the action of 

 their environments formed an important feature of 

 Lamarck's (Packard, '01; Cope, '96) theory of transmu- 

 tation of animal species. His theory is clearly in accord 

 with the material he studied most." The nature of his 

 contention and various well-known circumstances caused 

 his ideas not to be accepted. 



Characters used in classification of motile animals 

 before and since the time of Darwin are quite frequently 

 adaptation characters. Thus the large pectoral fins and 

 absence of an air bladder are characteristics of an entire 

 group of fishes, the darters. The divided eyes of the 

 Gi/rinidrr, which swim at the surface of the water, are so 

 adjusted that one half looks downward into the water, 

 and the other outward into the air. This character com- 

 bined with the paddle-like hind legs would have served to 

 distinguish the family. Again larvae with a head and 

 thorax modified to fit a circular burrow and with hooks on 

 the dorsal surface of the fifth abdominal segment, which 

 is supposed to be an adaptation to prevent the animals 



