DIRECTION OF LOCOMOTION OF THE STARFISH 



9 



a summaiy of the results of the whole set of experiments. In 

 the horizontal rows are recorded the results of trials with each 

 of the ten individuals. The vertical columns show the number 

 of trials in which the respective radii and interradii were in 

 advance. Inspection of the totals shows that on the whole there 

 was a considerably larger number of trials in which arm e was 

 in advance than any other arm or interradius. It will be noticed, 

 furthermore, that there is in general a falling off as one goes in 

 either direction from this position. This is shown more clearly 



TABLE 1 

 Distribution of crawling trials 



^ Through oversight only 49 trials were made with specimen No. 10. 



in figure 4, where the totals of table 1 are shown plotted in the 

 dotted line. In this figure the abscissal divisions represent 

 the radii and interradii from left to right, while each of the 

 ordinal spaces represents ten trials. 



If we consider all the movement in relation to the radii alone, 

 the preponderating direction of movement stands out some- 

 what more clearly. This may be done legitimate^ by appor- 

 tioning to each of the radii, in addition to its own records, one- 

 half of those for each of the adjacent interradii to right and left. 

 The result of such a redistribution is shown in table 2. It is 

 here easily seen that the preponderating direction in which star- 

 fish No. 1 crawled was with arm e in advance. The same is true 



