(1

Robinia pseudoacacia 1877

Oct 8' Older Plant in pot, not very healthy & leaves small.— Bristle fastened along terminal leaflet & end of petiole — made apparently several little circles, but marker not well fixed, so that tracing too small.

Another & rather younger leaf bristle fixed only to terminal last lateral leaflet moved very little down all day. At 3° I put mark behind closer & now the leaflet moved down & to the right; then a little down up & to right— & then to the right; but movement very small.

(Oct 9th a younger plant in Pot with finer leaves. — leaf facing light in study. Bristle fixed to along terminal leaflet viewed slightly obliquely — The leaflet rather old, late in season & did not hang down vertically when asleep — movements probably enfeebled. First dot 8° 14 last at 5° 28, when beginning to go to sleep. At 6° 15' fast asleep with bristle hanging highly inclined down. — By next morning at 7° 15' (Oct 10) had risen greatly as shown in diagram (1) & then moved to right or N. W & slightly down.— Tracing made on following day

(Diagram magnified: Vertical glass to tip of bristle 15 5/8 inch: Paper on stick behind bristle to tip of bristle 3 3/8: length of leaf 1 7/8: from base of leaf to tip of bristle 2 7/8: total distance from vertical glass to paper mark behind 18 6/8 inches)

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Robinia 1877

Oct 10. Made another tracing (2.) of same leaf; everything in same position: fell to 8° 45' & zigzagged till 9° 45', so very like yesterday & then fell steadily & obliquely: at 2° 5' I accidentally shook plant rather violently & on next observation was far to left —appeared to be in a state of tension — Soon after 4° out of field. It is probable that with younger & more vigour leaf, the morning zigzag wd have been much more pronounced, not likely the resemblance in — the 2 days accidental.