Pearl, Reactions of Limiilus. 163 



On the other hand, the phenomena in a case Hke the one under 

 discussion appear objectively analogous to certain phenomena 

 in the inorganic world. For example: one gets a complicated 

 piece of machinery fresh from the factory. If energy is put 

 into it it will do certain things. But on account of the new- 

 ness the parts do not work smoothly together. There is an un- 

 due amount of friction between the parts. As the machine is 

 used the bearings get worn a little and we say that as a whole 

 the machine " works better. " The continued functioning im- 

 proves the general coordination as a result of the interaction of 

 the parts. Objectively very much the same sort of change ap- 

 pears to take place in the behavior of a Limiilns embryo. Is 

 there any more of a psychical element in the one case than in 

 the other? This we obviously do not know, and it seems idle 

 to discuss the question, since no amount of a priori reasoning 

 will settle it and a posteriori evidence is not to be had. 



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'85. Notes on the Embryology of Limulus. Q. J. Micr. Sci., N. S., 



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'93. Ueber klinstliche Umwandlung positiv heliotropischer Thiere in 

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'72. The Development of Litnuliis polyphemus. Mem. Boston Soe. A'ai. 

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