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Show I' 52 CIROU:M:NU'rA'riON OF SEEDLINGS. CllAl'. I. mornm. g, bel!or·e l·t 'vas liO'ht they had risen to 59o above the 1' b ' f c1 1 . . the afternoon of the same day they were ouu 10l'lZOn; lU again horizontal. . · 1 Beta vulgaTis (Chenopodere).-The seodlmgs are excessive y sens1· t·1v e t'o 11· o·ht so that although on the first day they b , wore uncovered only durm· g t wo or. t,m· .e c Fig. 39. ,?\ ~ __ / ,/ Beta vu~qaris: circumnutation of hypocotyl, with filament fixed obliquely across its summit, traced in darkness on horizontal glass, from 8.25 A.M. to 5.30 P.M. Nov. 4th. Movement of bead magnified 23 times, here reduced to onethird of original scale. minutes at each observation, they all moved steadily towards the side of the room whence the light proceeded, and the t~·acino ·s consisted only of slightly zigzag hncs di;ectecl towards the light. On the next day tho plants were placed in a complo~cly darkened room, and at each o b~ervatwn were illuminated as much as poss1blo from vertically above by a small wax taper. The annexed figure (Fig. 3B) shows the movement of the hypocotyl during 9 h. uu~ler those circumstances. A second sccd1mg was similarly observed at the same ti~e, and the tracing had the same poculmr character, due to the hypocotyl often ~ovina and returnino· in nearly parallel hnes. The movement o/'a third hypocotyl differed greatly. \Ve endeavoured to trace the movements of the cotyledons, and for this purpose some seedlings were kept in tho dark, l!ut they moved in an abnormal manner ; they continued rising from 8.45 A.M. to 2 P.]t, then moved laterally, and from 3 to 6 P.)f. descended; whereas cotyledons which have been exposed tt~l the day to the light rise in the evening so . as to stan<l vertl~. cally at night; but this statement apphes only to younl? seedlings. For instance, six seedlings in the greenhouse ~ad their cotyledons partially operi for tho first time on the morwng of November 15th and at 8.45 P.M. all were completely closed, so that they might' properly be said to be asleep. Again, o~ tl:e morning of November 27th, the cotyledons of four other soodhngs, which were surrounded by a collar of brown paper so that they received light only from above were open to the extent. of ' . Jno· 39°; at 10 P.M. they were completely closed ; next moru b (November 28th) at 6.45 A.M., whilst it was still dark, two of them CIIAl'. I. RICINUS AND QUERCUS. 53 were partially open and all opened in tho course of tho moi·ning; but o,t 10.20 P.M. all four (not to mention nine others which had heen open in tho morning an<l six others on another occasion) were again completely closed. On tho morning of the 29th they wore open, but at night only one of tho four was closed, and this only partially; tho throe others had their cotyledons mnch more raised than dming tho day. On tho night of tho 30th tho cotyledons of tho four were only slightly raised. Ricinu,s Bor-b01tiensis (Euphorbiacero).-Soods were pmchasocl under the above name-probably a variety of tho common castoroil plant. As soon as an arched hypocotyl haclrisen clear above tho ground, a filament was attached to tho upper leg bearing the cotyledons which were still buried beneath the surface, and tho movement of the bead was traced on a horizontal glass during a period of 3t! h. The lines traced wore strongly zigzag, and as the bead twice returned nearly parallel to its former course in two different directions, there could be no doubt that tho arched hypocotyl circumnutatod. At tho clo~o of the 34 h. the upper part began to rise and straighten itself, dragging tho cotyledons out of the g]:ound, so that the movements of the bead could no longer be traced on the glass. Querc/J.s (American sp.) (Cupuliforre).-Acorns of an American oak which bad germinated at Kow were planted in a pot in the greenhouse. This transplantation chocked their growth; but after a time one grew to a height of five inches, measured to the tips of tho small partially unfolded leaves on the summit, and now looked vigorous. It consisted of six very thin internodes 'of unequal lengths. Considering these circumstances and the nature of tho plant, we hardly expected that it would circumnutate; but the annoxr.cl figure (Fig. 40) shows that it did so m a conspicuous manner, changing its course many times and travelling in all directions during the 48 h. of observation. The figure seems to represent 5 or 6 irregular ovals or ellipses. The actual amount of movement from side to side (excluding one great bend to the left) was about ·2 of an inch; but this was difficult to estimate, as owing to the rapid growth of the stem, the attach~d filament was much further from thfl mark beneath at the close than at the commencement of the observations. It deserves notice that the pot was placed in a north-east room within a deep box, tho top of which was not at first covered up, so that the insic~e facing |