[157]

Geotropism evident after 6° or 8° (in 2 lots) & subsequently after 21° or 23° increased greatly so the at roots vertically down down or very nearly nearly so No I, 8, 9, (13, after 8° at 45° after 23° reversed in same position.

Geotropism after 21° or 23° (& not at earlier hours) & w)

✔ nor. 4 after 21° angle of 45° & laterally quite vertical aft 45°

✔ 5. — quite vertical after 21°

7. after 23 terminal about 45°

12. after 23 almost perpendicular.

Retaining for some time Horizontal Position

(3) after 21° almost horizontal, but bent laterally, after 30° vertical.

(11) after 23° still horizontal

Then describe the 3 more remarkably cases.

(2) (13) (6) (10)

Geotropism prevailed ultimately in every case long enough observed, but much delayed in some of them, & a curious struggle went on.—

[157v]

(121

Phlox subulata Ch III

stands nearly in the throat of the corolla; whilst in the short-styled it is placed low down—sometimes very low within the throat, for it varies greatly in position. In this latter form the stigma often is more papillose, & longer than that of the long-styled forms, of greater length (in one instance in the ratio of 100 to 67), in the short-styled flowers than in the long-styled. My son measured 20 twenty pollen-grains from a short-styled flower, and of 9 nine from a long-styled, and the former were in diameter to the latter as 100 to 93; & this difference accords with the belief that the plant is heterostyled. But the grains from the short-styled varied much in diameter. He afterwards measured 10 ten grains from a distinct long-styled flower, and 10 from another plant of the same form, & these grains though appertaining to the same form differed in diameter as in the ratio of 100 to 90.

The mean diameter of these two lots of twenty grains was to that of twelve grains from another short-styled flower as 100 to 75; here, then, the grains from the short-styled form were considerably smaller than those from the long-styled, which is the reverse

[158]

Dates always from attachment of sqr.

(1) ✔— after 6° a little geotropic — after 21° greatly geotropic — after 30° vertically down.

(2) after 6° a little geotropic — after 21° kinked upwards— after 50' 45°' terminal portion vertically down so had made loop.

(3) ✔ after 21° almost horizontal, but bent from card a little laterally: after 30° terminal vertically down.

(4) ✔ after 21° bent down at about 45°, but also laterally — after 21° much more perpendicular & after 45° quite vertical.

(5) ✔ after 21° down & perpendicular so geotropism prevailed through

(6) after 6° a little geotropic — after 21° strongly contorted, for in the interval had risen & apex again bent down to angles of about 45°— after 30° terminal portion vertical.

(7) ✔ after 8° no geotropism: after 23° terminal about 45°

(8) ✔ after 8° slightly geotropic: after 23 terminal perpendicular

(9) ✔ after 8°….. do. almost perpendicular

(10) after 8° tip slightly geotropic: after 23° had risen above horizon & curled back towards the seed— if longer observed no doubt geotropic (like 6)

(11) after 8° no action & aft 23° still horizontal

(12) ✔ after 8° no geotropism action after 23 almost perpendicularly down.

(13) ✔ after 8° considerable geotropism ie 45° beneath Horizon — after 23° remained in same position.

[158v]

(120

Phlox subulata Ch III

(Phlox subulata (Polemoniaceæ)) Prof Asa Gray informs me, that greater number of the species in this genus have a long pistil, with the stigma more or less exserted; whilst several other species, especially the annuals, have a short pistil included seated low down within the tube of the corolla. In all the species the anthers are arranged one below the other in the tube, the uppermost was just protruding from the throat of the corolla. In Phlox subulata alone Asa Gray he has "seen both long & short styles; & here the short-styled plant has (irrespective of this character) been described as a distinct species (P. nivalis, P. Hentzii), & is apt to have a pair of ovules in each cell, while the long-styled P. subulata rarely shows more than one."* (*Proc American Acad of Arts & Sciences June 14 1870 p 248)

Some dried flowers of both forms were sent me by Asa Gray, & I received others from Kew, but I have failed to make out whether it is heterostyled. In two flowers of nearly equal size, the pistil of the long-styled form was that twice as long as that of the short-styled; but in other flowers there was no such differences in other case. The stigma of the long-styled pistil