IN a previous number of this Journal (NATURE, yol. lxvii. p. 569, April 16) an account was given of the results which had been deduced from a minute investigation of the percentage frequency of prominences as determined from observations made by Secchi and Tacchini at Rome, and Ricco and Mascari at Catania and Palermo. It was there shown that the chief centres of prominence action, that is, the zones in which the greatest percentage frequency of prominences occurred, indicated movements in heliographic latitudes, the general tendency of these being in a direction towards the solar poles, and not towards the equator, as is the case with the spots. Attention was also directed to the fact that these centres of prominence activity were not restricted to a narrow zone like the spots, which only occur between the latitudes ±50°and ±35°, but that at times they were numerous in such, high latitudes as ±8o°, and even higher.