Selection of the tactual reaction times upon which the mean is based, has been made with reference to the mode for each set of experiments. Inspection of the curves given by the reactions of each subject indicated that the great majority of the responses lay between 100 and 300σ, and that those which were beyond these limits were isolated and, in all probability, exceptional reactions due to some undetected variation in conditions which should throw them out of the regular series. On this account it was thought best to use only reactions between 100 and 300σ.
For convenience of comparison, again, the averages for the electrical reaction time of subjects A, B, C, D, E and F, and the same for the tactual reaction time of subjects 1, 2, 3, 4, 5 and 6 are herewith given together. All averages are for twenty reactions, except for D and 5, for which there are ten.
Besides the usual determination for the tactual reaction-time work on the six subjects named, there is given in Table XVI. the electrical reaction time of these animals to a two-cell current. Comparison of the electrical and tactual results are of interest in this case because the mean variation for each is about 34σ, being 34.3σ, for the electrical and 33.8σ, for the tactual.
TABLE XV.
| Frog. | Average of 20 Electrical Reactions. | Frog. | Average of 20 Tactual Reactions. |
|---|---|---|---|
| A | 149.5σ | 1 | 188.3σ |
| B | 158.3 | 2 | 199.1 |
| C | 191.0 | 3 | 212.1 |
| D | 167.0 | 4 | 213.0 |
| E | 182.4 | 5 | 199.8 |
| F | 176.3 | 6 | 221.9 |
| Gen. Avs. | 167.9 | 205.7 |
TABLE XVI.
REACTION TIME FOR TACTUAL AND ELECTRICAL STIMULI.
| Tactual Reaction Time. | Electrical Reaction Time. | |||
|---|---|---|---|---|
| Frog. | Average. | Mean Variation. | Average. | Mean Variation. |
| 1 | 188.3σ | 167.3σ | ||
| 2 | 199.1 | 180.1 | ||
| 3 | 212.1 | |||
| 4 | 213.0 | 210.3 | ||
| 5¹ | 199.8 | 138.5 | ||
| 6 | 221.9 | 164.4 | ||
| Gen. Avs. | 205.7 | 33.8 | 172.1 | 34.3 |
¹For 5 the average of ten instead of twenty is given.