(4

Keep

We may add that Mr

a pair of nearly opposite old & of the of younger leaves, that the distance was a little greater at night than in the day less during the day than at night ; (namely in the case of the older leaves by 1/41 of the nocturnal & of the younger leaves by 1/31 of the nocturnal distance; & this shows that the leaves had fallen or expanded by the early part of the night.)

[in margin:] (I think worth giving as movement in darkness)

This a cabbage which had formed Head same plant was left in the greenhouse until its head had become somewhat elongated (Nov. 10th) with the leaves not so closing pressed together; & a filament was so affixed to a leaf near to centre, 5 1/2 inches in length, & which stood ou t projected at 44° above the horizon Its movement was traced on a vertical glass, The plant being was kept in complete darkness, except for about a minute or two when being observed with every hour by aid of a tape. The movements were traced on a vertical glass. On During the final day, the leaf from 8° a.m to 10°. 40' P.m the leaf rose in a slightly zig-zag line; the actual distance travelled by its apex, being .67 of an inch (a) In the morning the By 7° a.m course of the night the leaf fell instead of rising & at 7° a.m on the following morning the apex had fallen .23 of an inch, & it continued falling until 9° 40' a.m. It then rose. until 10° 50' P.m; but the rise was interrupted by one considerable fall & reascent. During the 2d night it fell to a very short distance, rather inverted by the abnormally light & on the following morning after 6° 50' a.m reascends for a very short distance. The nocturnal night course of the movement of the line was thus altogether disturbed & distorted in [illeg]; & this [illeg] of the line originally lesser [drawn] This decrease in the amplitude of the movements no doubt depended on the plant having been kept for 2 days in darkness

[83v]

183

Ch IV Pontederia

Denchfield

(Pontederia sp? (Ponteraceæ))

Fritz Müller found this aquatic plant, which is allied to the Liliaceæ growing in the greatest profusion on the banks of a river in Southern Brazil.* (*Ueber den Trimorphismus der Pontederien'; Jenaische Zeitschrift Bd 6, 1871 p 74). It there exists under only two forms, in each of which 93 Denchfield which there are three long & three short stamens.

In the long styled form, the pistil (is was in two dried flowers sent to me) is in (length as 100 to 32, & the stigma as 100 to 80m compared with the same parts organs in the short0styled form. The long styled stigma projects considerably above the its own upper anthers in the same flower & staid on a level with the upper anthers of the short-styled form. In the latter the stigma is seated beneath both its own sets of anthers, and is on a level with the anthers of the shorter stamens in the long-style forms. The anthers of the longer stamens in of the short-style form are to those of the shorter stamens of the long-styled form as 100 to 88 in length. The pollen-grains distended with water from of the longer stamens in of the same short-styled form are to those from the shorter stamens of the same form as