On THH’s Lectures to working men.
Work by Ferdinand J. Cohn on the contractile tissue of plants ["Über contractile Gewebe im Pflanzenreich" Abh. Schlesischen Ges. Vaterl. Cult. 1 (1861)] seems important. CD has come to the conclusion that there must be some substance in plants analogous to the supposed diffused nervous matter in lower animals.
[Part of P.S. missing from original.]