14 J. K. WODSKDAI.KK 



end of the dish or the end nearest to me, and specimens B and 

 C were both at the ( — ) end, or the end farthest away from me. 



Columns II, III, and IV show the gradual formation of asso- 

 ciations in the three specimens. For instance, in column II 

 are given the names of the specimens which have eaten some 

 offered food, but would not follow it on the day opposite which 

 the names are set; column III represents the cases of the same 

 specimens when they followed the food as it was held near 

 their mouth -parts with a pair of forceps; and in the last column 

 are indicated the names of the same specimens which, when 

 present in the ( — ) end of the dish would swim to the ( + ) 

 end for food when I appeared or moved my hand over the dish, 

 and the letters A, B, and C, which represent the three speci- 

 mens, are placed in any one of the last three columns according 

 to the kind of behavior manifested during the different daily 

 observations. For example, on the fourth day of the experi- 

 ment letters A, B, and C, occur, in the second column which 

 means that on that day all three of the specimens ate an offered 

 particle of food, but would not follow it; nor did specimens B 

 and C which were at the ( — ) end of the dish, swim to the ( + ) 

 end when I appeared before them. On the twentieth day speci- 

 men A, which was at the ( + ) end of the dish, ate some food 

 but did not care to follow it; specimen B, which was at the 

 ( — ) end of the dish followed the food when it was held near 

 it with a pair of forceps and hence B is placed in column III; 

 and specimen C on the same date was also at the ( — ) end of 

 the dish, but it swam toward the ( + ) end when I appeared 

 and hence C was placed in column IV which is intended for 

 that type of reaction. 



It will be seen from the table that all three of the specimens 

 indulged in food within a few days, but that not until the end 

 of three weeks did all three swim after the food when it was 

 offered to them with a pair of forceps. The most obvious signs 

 of the formation of associations, recorded in the last column, 

 did not appear until even later. The number of cases showing 

 that form of behavior are noticeably less than those in the 

 preceding columns, but it must be remembered that during, the 

 last days of the experiment the insects occupied the ( + ) end 

 of their compartment the greater part of the time. Very fre- 

 quently when the nymphs were at the ( + ) end at the time 



