My dear Dyer

The fine lot of seeds arrived yesterday & are all sown & will be most useful.² If you remember pray thank M^r Lynch for his aid.³ I had not thought of Beech or Sycamore, but they are now sown.—

Perhaps you may like to see rough copy of tracing of movements of one of Cotyledons of Red Cabbage, & you can throw it into fire.⁴ A line joining the 2 Cot^s. stood facing N.E window, & the day was uniformly cloudy. Bristle was gummed to 1 Cot. & beyond it a triangular bit of card was fixed & in front a vertical glass. A dot was made in glass every $\frac{1}{4}$ or $\frac{1}{2}$ hour at point where end of bristle & apex of card coincided, & the dots were joined by straight lines. The observation was from 10^o A.M & 8^o 45^′ P.M. During this time the enclosed figure was described; but between 4^o P.M. & 5^o 38^′ P.M the Cot. moved so that the prolonged line was beyond the limits of the glass & the course is here shown by imaginary dotted line.—

The Cot. of Primula Sinensis moves in closely analogous manner, as do those of a Cassia.⁵ Hence I expect to find such movements very general with cotyledons & I am inclined to look at them as the foundation for all the other adaptive movements of leaves. They certainly are of the so-called sleep of plants.⁶ I hope I have not bothered you— Do not answer.—

I am all on fire at the work.— I have just had a short & very prosperous note from Asa Gray, who says Hooker is very prosperous & both are tremendously hard at work.—⁷

Yours very sincerely | Ch. Darwin