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Show 354 MODIFIED IRCUl\fNUT A'riON. 0UAP. VII. thers but only in Robinia with any care. Psoralea aca11lis ~aises 'its throe leaflets at nin-ht; whilst .Amor-pha f ruticosa,• Dalea alopecm·oides, and Indigofera . tin ct~ria depress them. Duchartro t states tha.t 'l 'ephrosia c~nbwa IS tho sole example of "folioles couch6es lc long du pctwle ct vers la base ;" but a Fig. li5. A. B. Lotus Creticus; A stem with leaves awake u·' ut~· mg th c d 3 ) , ·• B• with !ems a~lcep at night. SS, stipul e-like leatiets. similar movement occurs as we h avo a l r.e a dy seen' ::wd. shatl l again see in other case's . lV1.·s tan ·a S m· ens·t ·s ·, 'a. cc. ordm.0rr ..o , Royer t "abaisse les foliolcs qm. par uno d1's po.s itwn bJz.a no sont i' nclinecs dans la me• mo fum. 11 o, 1e s su p6neures vc1s 1e * Ducllo.rte, 'ElemcnLt; ue Botaniquc,' 1867, p. ::H.9. t Ibid., p. 34 7. t 'Aun. des S.C l·e nc.~ s. Nr.t s. Bot., (5Lh Hcrics), tx. 18u8. CHAP. VII. SLEEP OF LI~A VES. 355 sommet, les inferieures vcrs la base du petiole commun;" but the leaflets on a young plant observed by us in the greenhouse merely sank vertically downwards at njght. The leaflets are raised in Splu:erophysa saLsola, Ool1ttea Guborea, and .Astmgalus uliginosus, but are depressed, accordiJJO' to Linnrous, in Glycyrr·Mza. The leaflets of Robinia psrud(J-acacict likewise sink vertically down at night, but the petioles 1·ise a little, viz., in one case 3°, and in another 4°. Tho chenmnutating movements of a terminal leaflet on a rather olcl leaf were traced during two days, and were simple. The leafl et fell slowly, in a slightly zigzag line, from 8 A.M. to 5 P.M., and then more rapidly; by 7 A.M. on the following morning it ha.d risen to it8 diurnal position. There was only one peculiarity in the movement, namely, that on both days there was a distinct though small oscillation up aud down between 8.30 and 10 A.)f., an l this would probably have been more strongly pronounced if the leaf had been younger. Ooronilla rosr:a (Tribe 6).-Thc leaves bear 9 or 10 pairs of opposite leaflets, which during the day stand horizoutally, with Fig. 146. Coronilla rosca: leaf a ·Jeep. their midribs at right angles to the petiole. .At night they 1·iso up, so that the opposite leaflets come nem·Iy into contact, and t~ose on the younger leaves into close contact. At tho same t~e .they bend back towards the base of the petiole, until their DUdribs form with it angles of from 40° to 50° in a vertical rlane, as here figured (Fig. 146). The leaflets, however, somoa: es.bend so muc? back that their midribs become parallel to 10 ~on the petwle. They thus occupy a reversed position w t they do in several Leguminosre, for instance, in ..~.ltimosa 2 A 2 |
