OCR Text |
Show 300 1\IODI.FIED CIRCUl\1NUTA'l'ION. Cli.IP. YI. dicotyledonous series. A few remarks will have to be made about many of the plants in the list. In doino- so it will be convenient not to follow strictly 0 ' . any systematic order, but to treat of the _Oxahdre and the Leo·uminosm at the close ; for m these two Families 0 the cotyledons arc o-encmlly proviclccl with a pulvinus, and their movements endure for. a much longer time than those of the other plants m the list. List of Seedling Plants, the cof..rJledons of which rise or .~ink at night to an angle of at least 60° (tbove o1· beneath the honzon. Brassica oleracea. Cruciferro (Faro. 14). ---- napus (as we are informetl by Prof. Pfefler). . Raphanus sativus. Cruc1ferrc. Githngo segetum. Caryophyllcro (Fam. 26). . . Stellaria media (nccordmg to Hofmeister, as quotetl). Caryophyllere. Anocla Wrightii. 1\Jalvacere (Faro. 36). Gossypinm (var. Nankin cotton). Malvacem. Oxalis rosen. Oxalidu:: (~,am. 41). --- floribunda. ---articulata. --- Valdiviana. --sensitil·a. Geranium r otundifolinm. Gcra-niacere (Faro. 47). Trifolium subtcrraneum. Lcgu-mino re (Fam. 75, Tribe 3). ---strictum. ---- leucanthemum. Lotus orn ith opopoide~. Legnmi-n o~ro (Tribe 4). - - peregrinus. --Jacobreus. Clianthus Dampieri. Lcgumi-nosre (Tribe 5)-according toM. Ramey. Smithia sensitiva. Leguminosro (Tribe 6). Hrematoxylon Campechianum. Le-guminosre (Tribe 13)-accord· ing to 1\Jr. R l. Lynch. . Cassia mimosoides. Legum1nosre (Tribe l.J.). --- g lauca. --!lorida. --- coryrnbosn. --- pubcscens. --- tora. --n glecta. ___ 3 other 13r~zilian unnamed species. Bauhinia (sp. ?). Legumiuosre (Tribe 15). N cptunia olcracea. Lcguminosre (Tribe 20). Mimosa pudica. Leguminosre (Tribe 21 ). --albida. Cucnrbita oYi fer a. Cucurbitaccre (Fam. lOG). . ____ aurantia. Lagenaria Ynlgaris. Cucurb~taccre. Cucumis d uchtim. Cucurbit~~e~. Apium pctrosclinum. Umbelh eire (Faro. 11:3). ___ gravcolens. F Lact uca scariola. Compositre ( am. I 22). C sit·~ Helianthus annuus (?). o mp~. ' · I pomcea crerulea. Convolvu accre (Faro. 151). __ purpurea. __ bona-nox . __ coccinea. CHAP. VI. SLEEP OF COTYLEDONS. 301 List of Seedling Plants (continued). Solanum lycopcrsicum. Solanere (Fam. 157). Mimulus, (sp. ?) Scr~phul arin.ere (~'am. 159) -from 1nformatwn given us b_v Prof. Pfeller. . Mirabilis jalapa. NyctagmPre (Fam. 177). Mirabil is longiflorn. Beta vulgaris. l'olygoncre (Faro. 179). Amaranthus caudatus. A marnn-thaccro (Faro. 18v). Cannabis ~ativa (?). Canuabincre (Fam. 195). Brassica oleracea (Cruciferro ). -It was shown in the first chapter that the cotyledons of the common cabbage ri e in the evening and stand vertically up at night with their petioles in contact. But as the two cotyledons arc of unequal height, they frequently interfere a little with each other's movements, the shorter one often not standing quite vertically. They awake early in the morning; thus at 6.45 A.M. on Nov. 27th, whilst it was still dark, the cotyledons, which had been vertica.l and in contact on the previous evening, were reflcxed, and thus presented a Yery different appearance. It should be bomc in mind that seedlings in germinating at the proper season, would not he subjected to darkness at this hour in the morning. The above amount of movement of the cotyledons is only temporary, Ia.. ting with plants kept in a warm greenhouse from four to six days: how long it would lltSt with seedlings growing out of door. we do not know. Raphanus sativus.-In the middle of the clay the blades of the cotyledons of 10 seedlings stood at right angles to their hypocotyls, with their petioles a little divoro-cnt; at night tho blades stood vertically, with their bases in contact and with their petioles parallel. Next morning, at 6.4:".5 A.llf., whilst it ~as still dark, tho blades were horizontal. On the following rught they were much raised, but hardly stood sufficiently vertical to be said to be asleep, and so it was in a stillle s degree ?n the third night. Therefore the cotyledons of this plant (kept Ill the greenhouse) go to sleep for even a shorter time than those of the cabbage. Similar observations were made, but only during a single day and night, on 13 other eedlings likewise raised in the greenhouse, with the same result. .The petioles of the cotyledons of 11 young seedlings of &napis nigm were slightly divergent at noon, and the blades stood ~t right angles to the hypocotyls; at night the petioles W~re m close contact, and the blades consi<.lerably raised, Wlt~ their bases in contact, but only a few stood sufticiently npnght to be called asleep. On the following morning, .'. :; ,.,. ii |