[20]

Oct 30 (77)

Seedling Onions

(Used)

Long glass-filament fixed to stem & to diverticulum on distal portion which rises doubled back [sketch]

Kept in dark & traced on Horizontal glass; but the tracing failed for both points swept from wes N.E to S W so much that twice I had to move pot, & then by 1° moved off glass, & was so next morning— I can only conjecture that had in greenhouse bent to light & was recovering all day its upright position, through negative geotropism. N.B. The Cot. comes up doubled, with thickened places where doubled, & the distal part I call the diverticulum, & which has its tip decayed. — Perhaps glass rod interfered with free movement. — There were 2 or 3 zig-zags, but possibly due to shaking of pot when moved.—

Oct 31. observed again in same manner. The glass filament attached some way along the basal vertical portion & was 1.7 inches long, so that the angular movement of the basal part was much exaggerated, & the movement of its white tip was magnified 16.6 times on the horizontal glass the diverticulum & basal part of main stem moved nearly in same course.— Between 10° 18' & 3° 32', two very small circles were described, (ie in 5° 15') & between 4°. 50' & 10' course much considerably zig-zagged. I think no doubt nutations.—

A filament, 1.7 of an inch in length, was affixed almost

[Movement in plants, p. 60]