To Hubert Airy   10 [December] 1871¹

My dear Sir.

I am much obliged for your letter which has interested me; & the latter part has amused me much—² I did not know that Lowe was an Evolutionist; though he called here once & was very agreeable—³

Though the action of the Platysma is not really of much importance to me, yet out of a sort of obstinacy I am disappointed that I cannot find out whether it contracts during a shivering fit, which is the point about which I am most curious— I have lately had letters from 2 medical men in hospitals who have been looking out & never once had an opportunity for observation—⁴

With respect to Phyllotaxy I formerly wasted some time on the subject, but found I had not mathematical knowledge enough for the work. Your view of the form of the bud being an important element is new to me—⁵ A trustworthy observer, Nägeli, has made one important statement that in the bud the position of the young leaves is not fixed with accuracy,—but is subsequently determined as the shoot elongates a little.— Not long ago I hunted in vain for the reference to Nägeli, to give to M^r Chauncey Wright, who has read in the U. States & will soon publish a paper on this subject.— He is a mathematician, & thinks he has solved the problem—⁶ Whenever I receive his paper I will lend it you— The Rev. G. Henslow not very long ago published a paper on the subject, but as I had already given it up in despair, I cannot give you a reference— It could easily be obtained at the Linn: Soc:⁷

Believe me my dear Sir with thanks. | Yours sincerely. | Ch Darwin.