458 



A. M. Banta 



TABLE VT 



Sumnniry of the reactions of six Asellus communis and six Cacidotea stygia to mechanical vibrations 

 Produced by the concussions of bodies falling with -carious momenta. The body used in producing the con- 

 cussion, the distance of its fall, its momentum at the time of producing the concussion, and the grade of its 

 momentum, are indicated in successive horizontal columns at the top of the table. For each individual tested 

 are given in italics the total number of reactions obtained out of 20 trials for each momentum used, and the 

 sum of these reactions on the basis of their vigor. Following the summaries for the six pairs of individuals 

 are given in the last four horizontal columns the total number of responses, the average number of reactions out 

 of 20 trials, the average sum of the reactions for each 20 trials, and the averagevigor of the reactions for each 

 momentum used. For example, Asellus No. I gave 14, I J, 4, 4, I, I, I , o, 0, o, and reactions to the di^er- 

 Knt momenta used, and the sums of thevigor of these reactions were JJ, j6, 4,8 , 2, 1 , 2, o. O, o, and O 



BODY USED 



STEEL BALL 



Distance of fall in cm 501 



Momenta, in C.G. S. units '097 694 4711 347 



Grades of momenta 1:2 3 ' 4 



219 

 5 



83.6 50 30 30 lol 5 

 219 169 131 107 76 j 54 

 6 7 8 9 10 11 



No. of responses 14 



Vigor of responses : 33I 



No. of responses 16 



Vigor of responses 1 27 



No. of responses \ g \ 



Vigor of responses j 191 



No of responses 1 5 



Vigor of responses 1 6 



No. of responses I 5 



Vigor of responses [ 5 



No. of responses , 18 



Vigor of responses < I 



Total number of responses 67! 52! 



Average number of responses to 2C trials I lei Sji 



Average sum of the responses to 20 trials 18 173; 



Average vigor of responses 1' -^'i ^ I' -741 



8 j 14 



7 

 1 



•57 



No 



-Averaee vigor of responses to whatever stimulus, 1.79. 



