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Show 23G CIRCUMNUTATION OF LEAVES. OIIAP. IV· (10.) Acacia retinoides (Lcguminosro).~T~c movement of a young phyllode, 2~· inches in length, and mclm?d at a considerFig. 102. able anglo above the honr.on, was traced during 45 h. 30 111.; but in the figure hero given (Fi g.102), its circumnutation is shown during only 21 h. 30 m. During part of this time (viz., 14 h. 30 m.) tho phyllode Acacia retinoicles : circum nutation of a young phyllode, traced from 10.45 A.l'll. July 18th to 8.15 A.l'll. 19th. Apex of phyllode 9 inches from the vertical glass; temp. 161°-17t° C. described a figure representing 5 or 6 small ellipses. Tho actual amount of movement in a vertical direction was · 3 inch. The phyllode rose considerably between 1.30 P.M. and 4 P.M., but there was no evidence on either day of a regular periodic movement. Fig. 103. (11.) J,upinus speciosvs (Loguminosro). -Plants were misod from seed purchased under this name. This is one of the species in this largo genus, the leaves of which do. not sleep at night. The petioles rise d1rcct from the ground, and arc from 5 to 7 inches in length. A :filament was :fixed to tho midrib of one of tho longer leaflets, and the movement of the whole leaf was traced., as shown in Fig. 103. In tho course of 6 h. 30 m. the filament went four times up and three times down. A new tracing was then begun (not here given), and Lupinus speciows.: cir· during 12t h. the leaf moved eight times cumnutation of l~nl, up and seven times down; so that it traced on ver!lcnl described n ellipses in this time, and glas~ 4ft~omp\~·~5 ~:!~; to o. ;y • ·• this is an extraordinary rate of movement. <.luring 6 h. 30m. The summit of the petiole was then secured . 11 to a stick, and the separate leaflets were found to be contmua Y circumnutating. CHAP. IV. DICOTYLEDONS 237 (12.) Echeveria stolonijm·a (Crassulacero, Fam. 84).-Tbo older leaves of this plant arc so thick and fleshy, and tho young ones so short and broad, that it seemed very improbabl~ that any circumnutation could be detected. A :filament was fixed to a young upwardly inclined leaf, ·75 inch in length and ·28 in breadth, which stood on the outside of a terminal rosette of leaves, produced by a plant growing very vigorously. Its movement was haccd during 3 days, as hero shown (Fig. 104). The course was chiefly in an upward direction, and this may be attributed to tho elongation of tho leaf through growth; but we sec that the lines are strongly zigzag, and that occasionally there was distinct cil'cumnutation, though on a very small Ecl!cte1·ia stolonifera : circum-scale. nutation of leaf, traced (13.) Bryophyllum (vel Calanchce) from 8.20 A.l'll. June 25th cal to 8.4i"> A .l\I. 28th. Apex ycinurn (Crassulaccro). - Duval- of leaf 12t inches from the Jouve ('Bull. Soc. Bot. de France,' glass, so that the movement Feb. 14th, 1868) measured tho di's- wasmuchmagnified; temp. t 23°-2-l-!0 c. a~ce between tho tips of the upper ~aJrof leaves on this plant, with the result shown in tho following able. It should be noted that tho measurements on Dec. 2nd were made on a different pair of leaves:- Nov, 16 " 19 Dec. 2 8 A.M. 2 P.M. 15 mm. 25 mm. . 48 " 60 " • 22 " • 43 " 7 P.l\1. (?) 48 mm. 28 " fWuret hs ee from tl u·s T a bl e that the leaves stood considerably showso r tahp at rtt ha t 2 P. ·M · tha n a t 01' tJ ter 8 A.M. or 7 P.l\'I.; and this in th ~ a oy l'lso a little in the evening and fall or open e 10renoon. me~t·) trosem rotunrl?folin (Drosoracero, Fum. 85).-The movo( or g~ 0 da :ou~g leaf, having a long petiole but with its tentacles 47 h 1 a 5 n - earmg hrdrs) as yet unfolded, were traced durinO' large.l y mh: fi Th. e fi guro. (F'I' g . 105) shows that it circumnutatcdo 'c Ie Y m a vertical direction., making two ellipses each |