Can think of no suggestion to send to Mrs Forsyth. "The best plan is to read, think and speculate and then some suggestion or doubt will occur which can be determined or verified out of observation."

Asks her to probe worm-holes on grassy slopes with a knitting needle to ascertain whether they come out at right angles to the slope or to the horizon.

Thanks for observations on angles of worm-holes on slopes. William Darwin is observing at Stonehenge. She is worth her weight in gold.

Their enumeration [of forms of Lythrum?] is invaluable. He will write later to explain what he is trying to prove about Lythrum through laborious crosses.

Asks for flowers of both forms of Hottonia to measure pollen and compare stigmas.