My first and preliminary experiment consisted in putting seven leaves in the same vessel of water, and warming it slowly up to the temperature of 110° Fahr. (43°.3 Cent.); a leaf being taken out as soon as the temperature rose to 80° (26°.6 Cent.), another at 85°, another at 90°, and so on. Each leaf, when taken out, was placed in water at the temperature of my room, and the tentacles of all soon became slightly, though irregularly, inflected. They were now removed from the cold water and kept in damp air, with bits of meat placed on their discs. The leaf which had been exposed to the temperature of 110o became in 15 m. greatly inflected; and in 2 hrs. every single tentacle closely embraced the meat. So it was, but after rather longer intervals, with the six other leaves. It appears, therefore, that the warm bath had increased their sensitiveness when excited by meat. I next observed the degree of inflection which leaves underwent within stated periods, whilst still immersed in warm water, kept as nearly as possible at the same temperature; but I will here and elsewhere give only a few of the many trials made. A leaf was left for 10 m. in water at 100° (37°.7 Cent.), but no inflection occurred. A second leaf, however, treated in the same manner, had a few of its exterior tentacles very slightly inflected in 6 m., and several irregularly but not closely inflected in 10 m. A third leaf, kept in water at 105° to 106° (40°.5 to 41°.1 Cent.), was very moderately inflected in 6 m. A fourth leaf, in water at 110° (43°.3 Cent.), was somewhat inflected in 4 m., and considerably so in from 6 to 7 m.