Table I gives these averages for all the fourteen negatives. In four of these (H 2, H 3, Tu 1, Tu 2) simultaneous curves for both eyes were obtained. In every curve the slow eye-movements were in the same direction as the previous rotation; the rapid in the opposite direction. The very few single movements that are exceptions to this are noted under Table II. Had the photographs been taken during (instead of after) the rotation, the directions of rapid and slow movements would undoubtedly have been reversed. It is to be noted that when both eyes were recorded, their movements were generally identical, within the accuracy of measurement (one sixtieth of a second). There are a few exceptions to this. The averages of all slow and all rapid movements merely show that in general, and for that part of the nystagmus that was photographed, the slow eye-movements lasted six times as long as the rapid ones. This ratio varies considerably from one case to another, and at best throws little light on the whole nystagmiform series, since during the very first instants after the rotation the ratio of quick to slow movements would be less than one sixth, and at the very end of the series would be considerably more; this because toward the end the slow movements become much slower, while the rapid seem to change very little. The variations from case to case arise, at least partly, because in some cases the picture was taken more promptly, after the rotation stopped, than in others. TABLE II All records in seconds. Subject C. Subject H. Subject H. Subject Tu. Film 3. Film 2. Film 3. Film 4. anti-clockwise. clockwise. clockwise. anti-clockwise. right eye. left eye. right eye. left eye. right eye. right eye. slow fast slow fast slow fast slow fast slow fast slow fast m. m. m. m. m. m. m. m. m. m. m. m. to to to to to to to to to to to to lft. rt. lft. rt. lft. rt. lft. rt. lft. rt. lft. rt.