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inflected. So it is as we shall see hereafter see with the sensitive filament six filaments on the leaves of the [4 penciled lines illeg] Dionæa, which are exquisitely sensitive to to an instantaneous & most delicate touch, even from a hair. — I have been struck with the same fact (as will be clear in a future paper) in the case of the tendrils of some climbing plants. According to * the irritable stamens of Berberis are not affected by drops of water falling on them. In all these cases we should bear in mind, that cases the most probable view appears to be, not that the tissues have gradually been rendered insensible to drop of water or rain falling on them, but that they were originally rendered, for the benefit of the plant, highly sensitive to the contact of any solid object. We should bear in mind that there is good reason to believe * (*quote section from Cohn & refer to new Edition of Origin of Species) that all vegetable cells are in some slight degree affected or excited by contact, & that this quality has been

[in margin:] The case of the Mimosas & Acacias, Trifol & Oxalis make me think that aboriginally plant wd be equally sensitive to water & winds I think all these had come in separate discussion with [illeg] & [illeg]

[in margin:] Keep for Bloom

(Kerner Die unberufene gaste Lettuce-leaves sensitive to ant tarsi)

over

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greatly increased in these plants which are highly irritable. Extreme excitability to the contact of a solid object having been are acquired, it incidentally follows that the cells are likewise strongly excited by other stimulants to which they are naturally never exposed, such as a current of electricity, a burning heat & various chemical reagents.