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May 26th 1878.

Geotropic movement Amphicarpaea Monoica

Plant forced to trail on ground— A cleistogamic flower I think me mere buds?? on short peduncle had bowed over & had buried itself about 2 /10' inch deep in loose sand. Buried itself this much in about 24° was raised up an inch above ground & stem secured on each side to stick— Glass filament fixed transversely on flower, with mark below, & traced on Horizontal glass— illuminated feebly only from above. [sketch] — The peduncle when thus [illeg] pointed instead of pointing perpendicularly down now stood between 20° & 30° below horizon— Distance of bead of sealing wax from mark below. .37 of inch (if this distance lessen will show that Geotropism is acting — Peduncle so short & flower(?) so minute must be geotropic.

[in margin:] Remember is a Twining Plants

May. Traced movement of one of these buds from 9° a.m on 26th to 9° 30' on 27°. See Tracing. Much magnified— Shoot or Peduncle first moved downwards & then upwards with very little lateral movement. After 9° 30' on the 27th to 9° on the 28th the bead moving little circle too small to copy — Perhaps my study too cold.— I have dissected the one to which glass filament attached & 2 other, & they seem mere buds: if there be any flower-bud in centre it must be excessively small for I could not discover it, though there were many buds.—

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Amphicarpaea

June 23d I find the long thin branches penetrate the ground like roots for at least 1 3/4 inches (& I imagine flower under ground) They are coated with reflexed hairs which must aid in penetration, & perhaps circumnutation may aid them.

(July 10th ؟؟ Many branches which have penetrated the ground are now quite thick, & I found one which came out of ground again — I presume some these branches produce flower & the subterranean pods— Many little branches point vertically down (& which were before observed & f to nutate — Other long branches twine— I this day July 10th put white cards with holes to see if the geotropic branches direct themselves to dark points. —)

Augst. 5th— only long runners or climbers seem now produced.