Certain absorption lines in the spectrum of W Virginis have been found to be double during a short phase interval centred approximately at light maximum. They behave as if a sequence of velocity variation starts abruptly with the appearance of lines showing high velocity of approach, just before light-maximum and while the lines of the preceding sequence showing high velocity of recession are still present. As the sequence continues, the lines, which at first showed high velocity of approach, move longward until they in turn show high velocity of recession. They do not disappear until the next light-maximum, by which time another velocity sequence is well advanced. The duration of a velocity sequence is thus from shortly before one light-maximum until shortly after the next.