ACTINIAN BEHAVIOK 225 



not to the effects of past rhythmic stimulation. As a result of 

 their various activities their physiological states are changed 

 and these changes unquestionably modify their capacity for 

 renewed response, but such changes are probably not very pro- 

 found nor long lasting. From the evidence thus far accimiu- 

 lated, it appears that these states persist for only a brief period, 

 often only a few minutes or at most some hours. It also appears 

 that an actinian is much more nearly an organism whose internal 

 state is one of general uniformity than one of great flux. On 

 this uniformity as a background the changing environment calls 

 forth now this now that set of responses without, however, 

 seriously disturbing the internal equilibrium. This condition of 

 affairs is in strong contrast with what is found in the higher 

 animals, where the responses to the enviromnental influences 

 are extremely diverse and variable in consequence of the internal 

 states, and as a result these animals when subjected to experi- 

 mental study often exhibit such novel and apparently unrelated 

 responses that we are prone to speak of many of them as acci- 

 dental or spontaneous. Spontaneity in this sense is not a char- 

 acteristic of actinian behavior, which recalls very much more 

 the relatively simple direct type of reaction as seen in such 

 organs as the vertebrate heart. It is with this type of reactive 

 mechanism rather than with the cerebral cortex that, in my 

 opinion, the actinian shows affinity. 



If such a view of the behavior of sea-anemones is correct, 

 there is no reason to suppose that the unity of their organization 

 is necessarily of a high order, as in fact the preceding accounts 

 show. I am fully convinced that von UexkiiU's description ('09, 

 p. 75) of one of these animals as a bundle of reflexes is inade- 

 quate, but I am also fully convinced that this description is 

 nearer the truth and certainly far freer from error than the pic- 

 ture drawn by Gosse. ('60, p. 82) of these forms endowed with 

 consciousness and will. The facts that the pedal half of an 

 actinian may creep normally without the oral half and that the 

 oral half is responsible for the feeding activities through a con- 

 course of semi-independent parts, tentacles, esophagus, and so 

 forth, make it quite obvious that the organic unity of the animal 



THE JOURNAL OF EXPERIMENTAL ZOOLOGY, VOL. 22, NO. 2 



