My dear Father,

I shall have lots of time to do the oats & will sow some next week.² Also I can easily see about sleepers. Porliera hygrometrica is the plant & belongs to the Zygophylleæ.³ There is something odd about it I found that a twig in water in the room was open while the plant in the garden was shut, & it does not depend on light only as a twig kept under water in a glass & in blazing sun, was quite open. I have seen a few plants that look as if they must sleep & I will go round the garden carefully in the evenings when I always go a loaf.

I think the great distinct Pfeffer makes is between sleepers with joints & those without joints, & says that there is no growth but only variation in tension in those that have joints. But Batalin says there is very slight growth even in those with joints.⁴ It seems an absurd thing to call the two really different. I will see what Sachs⁵ says. If possible I will do the microscoping here. I have been cutting sections of roots to see the development of secondary roots & I shall know enough to make out the anatomy of the bean roots if it is wanted. Today I did the male & female organs of Marchantia⁶ & tried the prothallus of a fern but failed, the great thing is not so much very thin sections, but

⁠⟨⁠at least 2 pages missing⁠⟩⁠⁷

like this

so that they move up not down at night⁸

I must leave off & measure my roots⁹

Your affec | F D

(ought I to call on Semper?)¹⁰