For many years the author has wondered why the Portuguese Manof-war (Physalia pelagica Bosc.) is so oriented physically that it is consistently driven by the wind about forty-five degrees to the left of the direction in which the wind is blowing (Figure 46, left). Records kept of this leftward tendency showed little variation in distribution or time, within the limits shown in Table I. In the literature concerning this animal no explicit reference to this question of its motion relative to the wind and water has been found.