Use of the tapping test as a measure of the decrease in tendency to fatigue similarly brings out no indication of any improvement in the operative group of cases. The measure of fatigue was taken as a ratio; namely, the number of taps in the first, minus the number in the second half minute over the number of taps in the first half minute. Then, if there is a greater number of taps in the second, the ratio will be minus, indicating that fatigue effect is so small as to be overcome by practice effect. This was a fact in only four cases. Since what we are measuring is improvement, the ratio for test 2 is subtracted from the ratio for test 1 to find the gain in overcoming fatigue. Table VIII shows the average gain for group one to be -.0196, and the median -.045. That is, there is an average increase in fatiguability of .0196 units and a median increase of .045 with a P. E. of +- .02. This increase in fatiguability occurs also in the control group, average 0, and median .03 with P. E. of +- .03. The average gain of test group over control group is -.02 and the median gain is -.015. Again variability is relatively large, P. E. being 1.04, so that the median and average gains are -.50 P. E. and -.38 P. E. respectively. We may say, then, that the capacities brought out by the tapping test seem to undergo no improvement in six months after removal of adenoids and tonsils. The main line of interest in the present experiment lay with the relation of adenoid and tonsil defects to general intelligence. The results of the two tests dealing more specifically with this side of the problem are here set forth. Table IX shows the I.Q.'s. of the two groups before and after the six months' interval, together with changes plus or minus in I.Q., and a comparison of the separate pairs in respect to improvement. We find that the test group shows an average gain in I.Q. of 2.25 points. The median gain is 2 points, the total range 18 points and P. E. of the average is +- .99. The control group shows an average gain very slightly higher, 3.25 points, the median gain being 3. The range in this case is 32 points, but P. E. is only +- .47. The average of the compared gains of separate pairs is -1.035. These numbers are so small as to be insignificant. Actually, we may say that the operative group as a whole showed no gain over the control group. If we examine individual cases we find that the greatest loss in I.Q. was in the control group, (8 points) but the greatest gain (24 points) also appears in this group. In the test group 11 cases TABLE VII Gain in number of taps in one-half minute, 21 pairs--right hand N[16] Test Group (A) Control Group (B) Test 1 Test 2 Gain Test 1 Test 2 Gain A-B