(1

Saxifraga sarmentosa

A pot with thin runners more than a foot in length hanging down on all sides perpendicularly. — Two tied up almost vertically, but their upper ends bent down so slightly after several days that I think curvature due chiefly to mere weight—  One 17 1/2 inches long still tied up but with distal part depending yet considerably above horizontal had thin stand strand [sketch] fixed to tip & its movement traced on vertical glass; certainly circumnutate a little, rising & moving during day to one side & then back, then again back & then upwards; but on next day moved very slightly from growth seem arrested by straw fixed to tip.—

A second runner 10 1/4 inches long & thicker was traced at same time on vertical glass; see Tracing (I) it moved first up & to left then to right & up & then parallel back & down; up again; to right & then back & parallel. so changed course 5 times completely  Next morning (18th) was off vertical glass, as it had risen so much & this show how little affected by geotropism & it movement now traced on Horizontal glass in darkness See Tracing (II.) Magnified 2 1/5 times = 2.2 — & the movement in line of arrow implies rising  The tip made rather more than 2 ellipses between 7° 45' a.m. & 11° P.m, & the point tra the extreme actual distance travelled by point was almost above .75 of inch or 3/4 of inch. It is not likely that under Nature the runners

(See Back)

[1v]

The thick runner's growth was delayed in passing through the forest of pins, & this part, now slightly sinuous thicker than the older part.

(Stones on ground)

(2

Saxifraga umbrosa Sarmentosa

In a state of nature the stolons freely grow along the ground, so that can hang-down & probably travel laterally on earth in midst of vegetation & the circumnutation of point much aid it in finding path.—

(Ap. 24th I put a forest of rather large pins several scores always close together in front of tip of thick runner it penetrated amongst them, but could not get in, the tip then rose & the part beyond or rather within the forest become bowed; the tip then found a passage high up between the pins & again descended & at last got through. At one time it bent at right angles to its former course; ultimately the stem was permanently slightly sinuous.— Two very thin lateral runners got through another forest of pins much more easily‒  I think no doubt circumnutation must aid such penetration, though I do not say this cause of circumnutation.

By scratching lines of damp-sand it was clear that the runner circumnutated whilst going on it.

Smoked glass

The forest of Pins