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Observed from morning of 13th to night of 16th

Carnation Dianthus caryophyllus

circumnutation of leaf

A Carnation trained to into tall stem, with vigorous growing terminal shoot. The young leaves emerge vertical, but rapidly bend downwards, this terminal part becoming afterwards soon almost horizontal, & ultimately bowed downwards— In thus changing their position, they often bend to one side & become slightly spiral.

A young leaf was selected which stood very highly inclined & & at end of observation it was 5 1/4 inches long, with glass-filament attached to apex, observed under skylight— [sketch]

Apex after it had become horizontal was 8 3/4 inches from vertical glass—

First observation on 8° 35' a.m on 13th, when highly inclined, but by morning of the 14th had become sub-horizontal. This must be due, I think, to geotropism, for leaves moderately stiff & & do not afterwards for some time bend downwards—; but the growth of axis may aid in pushing outwards & downwards leaf.

This case is interesting, as we see that the line on the 13th was zig-zag i.e modified circumnutation from morning morning, of 14th to night of 16th. leaf travelled some distance to left, in extremely zig-zag course, & occasionally circumnutated in a manifest manner.

Temp. on 13' 16 1/2 to 17 1/2 / 14' 16° 1/4 / 15th 15—15 1/2 / 16' do.