Down, | Beckenham, Kent. | Railway Station | Orpington. S.E.R.
Jan 20
My dear Gray
This is a P.S. to yesterday's letter to say that the drawing at
p. 21 of your text Book wd. represent
perfectly all that I have seen, supposing that a line were drawn, representing the
surface of the soil, 12 inch above the seed, assuring that the seed had been sown at 12 inch depth.— You may perhaps like to hear that the first true
leaves break out through a split at base of confluent petioles of Delphinium
nudicaule presicely as in Megarrhiza. The swelling of the plumules bursts the
tube, & then the bowing downwards of the tip of the plumules of Megarrhiza,
forces it laterally out of the tube. The tip is at first straight.—
This bowing down of the tip is a very common or rather universal movement with
seedlings, but here it plays a new part.
Ever yours | C. Darwin
