My dear Oliver—

Will you be so kind as to give me your opinion on the following point? I was so much struck with the corresponding position of tendril & flower stalk in Passiflora that I got my son William² (who can dissect under a $\frac{1}{\mathrm{<xtf:hit\; score="100"\; rank="1"\; hitnum="1"\; more="no"><xtf:term>10</xtf:term></xtf:hit>}}$ & can draw) to examine these parts in their earliest stages. In the enclosed drawing (which please to return) you will see Fig. 1 the tendril & flower bud apparently quite confluent which seems odd.³ From Fig. 2. to 7 you will see the gradation. The sort of horn to the left is the outer division of the involuca which in the early stages is the most developed.⁴ In one single case of an old bud Fig. A my son found the top of the tendril absolutely like a flower bud in an early stage as in Fig. 3 or 4.⁵

Does not this render it highly probable that the tendril is a modified flower with its peduncle?⁶ I presume that a flower w^d be called by you an axillary part??⁷ & that in the vine the tendril might be considered a modified flower peduncle as I now see Lindley maintains that it is.⁸

It w^d I have reason to think be a considerable relief to me, if I might view such tendrils as modified flower stalks instead of modified branches⁹

Pray tell me is there any essential distinction between the peduncle & mid rib of a leaf, & a branch? for does not a leaf some times produce buds?¹⁰

It w^d a great kindness if some day you w^d look at the plants of Tecoma Radicans & observe if the branches spirally twine—¹¹ I suppose they do not—

Also w^d ⁠⟨⁠y⁠⟩⁠ou look at Tecoma Undulata & Capensis— How can they climb? Do they twine or do they emit rootlets like T. Radicans? My plants tho’ 4 f^t. high shew no signs of climbing.¹² I am much interested about the Genus Tecoma.

Believe me dear Oliver | yours very sincerely | Ch. Darwin