[104]

Rubus Hybrid between R. idæus & an American Species.

(Plant 11 inches high.) about 18 1 foot High

March 18' to morning of 20' Apogeotropism

Pot laid Horizontally — vertical glass— very dimly illuminated only on front, & only effect of this cd be to delay apogeotropism.

Traced from 10° 40' a.m on 18th to 8° a.m 21' all After 12° 5 began to rise, & continued so till 10° 40' P.m, at first rapidly & then slowly, with hardly a trace of circumnutation During night also rose. — next day 19th rose in zig-zag lines showing some circumnutation.— On 2d night also rose, on next day circumnutated greatly so that figure so complex it cd hardly be traced: between 7° a.m & 10° 30' or 15 1/2 h P.m, went at least 4 times to right & 4 to left, & 3 times up & 3 times down. . On this night & next morning was still rising.— Glass filament at end of shoot was now 49° 67° above horizon; when started shoot horizontal.

We here clearly see that whilst apogeotrop acts energetically it destroys circumnutation completely, but as soon as it acted less energetically on 2d day (for shoot rose less) it clearly zig-zagged, & on third day. though still rising it regularly circumnutated up & down & laterally — Was still rising on morning of 4th day

Whilst zig-zagging on 2d day rose vertically very unequally in equal times due probably to growth on conve concave side.—

It is obvious that during whole 3 & 1/2 days apogeotropism was acting & modifying in less or greater degree circumnutation.