My dear Dyer.

It was very very good of you to have taken such great trouble about the cotton-seeds. Some of those from Naples show this day their noses above ground, & I have no doubt will serve my purpose excellently.¹ I hope my work will some day end, but new points are continually turning up.

I am now observing the germination of the Cucurbitaceous genus Megarrhiza, & it is a very curious case, for the petioles of the 2 cotyledons (which never break out of the seed-coats) unite & form a hollow tube which penetrates deeply into the ground, & becomes functionally (& structurally as far as surface is concerned) a root; the plumule bursts the tube at a depth of 2–3 inches beneath the ground & then rises to the surface.—²

Ever yours sincerely | Ch. Darwin.

You are an unfortunate man: writing about Megarrhiza has made me think that I ought to look again at the germinating seeds of Trichosanthes anguina or I daresay any Trichosanthes, for I record in my notes that “cotyledons fleshy almost like hypogean ones”. Therefore the hypocotyledonous stem ought not to be provided with that wonderful peg or heel by which the seed-coats of most other Cucurbitaceæ are torn apart beneath the ground, & which I was delighted to find quite absent in Megarrhiza.³ Am I not a superb bore?!

Can you give me seeds of Trichosanthes; but do not write.—