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Show 208 CIRCUMNUTATION OF STEMS. CIIAP. IV. they were found to be still circumnutating, but on a yet smaller scale. (12.) Gazanict r1'ngens (Compositre, Faro. 122).-Tho circum-nutation of the stem of a young plant, 7 inches in height, as measured to the tip of the highest loaf, was traced during 33 h., and is shown in the accompanying figure (Fig. 78). Two Fig. 78. I I I I I / i I . '.loo :npan,.2zt! Gazania rinaens: circumnutation of stem trnced from 9 A.M. :March 21st to 6 P.M. on 22nd; plant kept in darkness. Movement of Lead at the close of the observations magnified 34 times, he1·e reduced to half the original scale. main lines may be observed running at nearly right angles W two other main lines; but these are interrupted by small loops. (13.) .Azalea Indica (Ericinere, Faro. 128).-A bush 21 inches in height was selected for observation, and the circumnutation of its leading shoot was traced during 26 h. 40 m., as shown in the following figure (Fig. 79). (14.) Plumbago Gapensis (Plumbagincro, Faro. 134).-A small lateral branch which projected from a tall freely growing bush, at an angle of 35° above the horizon, was selected for obser· vation. For the first 11 h. it moved to a considerable distance in a nearly straight line to one side, owing probably ~ i~s having been previously deflected by the light whilst standmg Ill the greenhouse. At 7.20 P.M. on March 7th a fresh tracing was begun and continued for the next 43 h. 40 m. (sec Fig. 80). During the first 2 h. it followed nearly the same direction n.s before, and then changed it a little; during the night Jt moved at nearly right angles to its previous course. Next CHAP. IV. CIRCUMNUTATION OF STEMS. 209 day (8th) it zigzagged greatly, and on the 9th moved irreO'ularly round and round a small circular space. By 3 P.M. 0 on the 9th the figure had become so complicated that no more dots could be made; but the shoot continued during the evening of the 9th, the whole of the lOth, and tho morning of the 11th to Fig. 79. \\\, \\\1> ', ', Azalea Indica: circumnutation of stem, illuminated from above, traced on horizontal glass, from 9.30 A.M. March 9th to 12.10 P.M. on the lOth. But on the morning of the lOth only four dots were made between 8.30 A.M. ~nd 12.10 P.M., both hours mcluded, so that the circumnutation is not fairly reprcs~ nted in this part of the diagram. Movement of the bead. here magnified about 30 t1mes. Fig. 80. ~ I I ---~ Plumbago Capansis: circn~nutation of tip of a lateral branch, traced on horizontal glass, from 7.20 P.M. on Mar ch 7th to 3 P.M. on the 9th. Movement of beau magnified 13 times. Plant feebly ill uminatcd from above. cthier cu.lm..thnu tate ov e~. the same small space, which was only about bran2h . of an mch ('97 mm.) in diameter. Although this Co c fcll'cumnutated to a very small extent yet it chan()'ed its maugr se'f i rdc qu en tl y. Tho movements ought to' have beeno mor n1 e . (15.) Al · · · l 'ng fi oysta cttnodora (Verbenacere Faro. 173).-The follow-gure (F'J g. 81 ) gi·v es the movem' ents of a shoot durino· 0 p |