326 WILSON GEE 



Just how the mucus secretion affects the responsiveness of the 

 muscular fibrils has not been determined in the present work. 

 There seems to be a disturbance of the balance of nutrition in 

 the cell and the muscular fibrils of that cell suffer as a conse- 

 quence. An important agency in effecting the lowered tonus 

 would seem to be a withdrawal of nutritive materials from the 

 muscular elements and the tentacles hang flaccidly along the 

 edge of the disk. The relation of the neurofibrillar system of 

 the anemone to the secretion of mucus is scarcely possible of 

 determination. There is a possibility that the changed respon- 

 siveness in the anemone may be due to the effects produced in 

 the neurofibrillar system by the chemicals employed. There 

 may be even a condition similar to anesthesia produced. 



It would certainly seem to the writer that from the data 

 presented in this paper, there is no valid ground for stating 

 that the modified behavior in relation to food is due, as Jennings 

 (1905) contends, to the animal's acting as a unit in "satiety." 

 If the general condition of satiety affects the organism as a 

 "unit" why should it be that even a f ter being gorged with food, 

 the gastrovascular cavity ejecting the material through the 

 mouth opening, the mouth continues to accept food? And why 

 is it that the tentacles of the animal can be made irresponsive 

 to food without any of this food entering the gastrovascular 

 cavity? Then, too, Parker (1896) has found and Jennings 

 (1905), in certain cases, as well as Allabach (1905) and the 

 present writer that upon the tentacles of one side being fed to 

 refusal, the tentacles of the opposite side of the disk will. accept 

 food. The view that the seat of the modified responsiveness 

 lies very largely in the individual tentacles is more clearly in 

 accord with what is known of the structural organization of 

 the sea anemone than that the animal acts as a unit. The suc- 

 cessive applications of pieces of food, through the accompany- 

 ing mucus secretion serves to lower the responsiveness of the 

 tentacles, and a gradual decline in this responsiveness is pro- 

 duced till finally the feeding response fails entirely on the part 

 of the tentacles. 



SUMMARY 



The species of anemone studied, Cnbrina xanthogrammica 

 Brandt usually remains expanded during the day and contracted 

 during the night. It is suggested that the presence of numerous 



