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These flowers stand in pairs with right-Hand & left-Hand projections

July 18th Calathea longibracteata flower sent from Kew— touching folded filament with hair or bristle does not start it, or deeply pricking pistil, but a very slight push outwards (as insects wd do) of the filament frees the pistil & so I have no doubt that it is the action is purely mechanical, & if so it is probably the case with Thalia—

Maranta Luschnathiana behaves, I believe, in same way.—

(If first flower open of Calathea, try again— with hairs— or acid — or chloroform drips of.

Case like Isotoma

Minute Drop of N. Acid did not cause explosion; but do of Chloroform did do so— but as filament is folded up into tube, it seemed to draw the fluid to base of petal & chloroform causes petals to curl & this wd free clasp.—

[12b]

Calathea.

I tried repeatedly with Right & Left-Hand flowers (for some have filament on right & some on left) in some respects parallel case to that of Thalia) & the filament on spur which is stiffish can be bent towards centre of flowers & which keep clasp on pistil, without exploding, but in the least bend in opposite direction causes explosion.—

If hole drilled gently low down pistil, it is such a state of tension that it breaks itself & the upper part curls upwards without freeing itself from hood— everything shows mere mechanical action.— Repeated experiment with same result.

Fibro-vascular bundle in folded filament

Enfolding petal not so stiff as I shd have expected — though rather more so than in Thalia.— Pistil most curious in rigidity like Dionæa after exploding; for it is here very stiff though not so stiff as in Thalia

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19th July

Thalia

I cut away part of shield & pressed with cut-off-head of fine ent. Pin on the shield, & it exploded after doing so once or twice.— I cannot conceive that I could have pulled shield away— Moreover sensitive filaments are generally pushed against wall of flower & if they were to act as levers they must be pushed still furth in same direction.

I touched clasp of another fl. repeatedly before it exploded with point of needle pressing on it— at last it exploded— I think I could not have pressed it at all from the pistil so as to have caused it to slip off.—

In another fl. I bored the sensitive filaments & smashed the tips with pincers & pistil did not explode, but when I touched clasp off it went.—

In another flower, I touched the clasp. with cut-off square end of fine ent. pin, in such a direction, that I believe I

[13b]

I believe I could not in the least have pushed off clasp, yet it instantly exploded— young flower with great drop of nectar about the clasp. — The strongest argument is the position of filaments, so that insects cannot push them in f manner to with draw clasp.—

July 20th 8º. 30' a.m To day in turning back one of true petals exploded— also its other flower, after cutting shield in turning it back— This flower was not open at 4º P.m yesterday.— Seeing how insensible the sensitive filaments have lately been & how easily the pistil explodes all spontaneously or by slightest jar— may not the late flowers have become more adapted for self-fertilisation, when probably less visited by insects.—