[41]

(Used)

Marsilea: 6 leaves exposed for one hour—; the pot was placed on the ground on a blanket which was wrapped round the part of the plant which hangs down & which therefore trailed on the ground but the mass of leaves hanging at the edge of the pot was exposed to radiation. Next morning all 6 utterly killed

On the rest of the plant about 12 were killed. Of these 12, three were known by marks to be those which had got to look unhealthy from being pinned out ready for a frost for a long time. There were 5 thus pinned out, & it is possible that all 5 were comprised in the 12 killed. The five old pinned ones were not utterly unhealthy however as at least one of them went to sleep the night it was unpinned. Owing to the rug being over some of the plant it is impossible to say how many leaves (not pinned) were exposed; but the general impression given was that a very small percentage of un not-pinned ones were killed.

see p. 7 other paper & preliminary trial give this at end Also p 3