From Francis Darwin   [26? October 1873]¹

1   Enormously the largest number of Desmodium are trifoliate; some are unifoliate tre and uni leaves sometimes occurring in the same plant—² In the uni ones the stipellæ of the lateral leaflets could not be seen— There were no intermediate leaves between uni & tri these lat: leaflets are either present & of normal size or quite gone— The general relation between lat & term leaflets which exists through the whole genus (except D gyrans³ and a very few others) is this; the terminal leaflet is bigger than the lateral ones about in the propⁿ term is to lat. as 7-:6- D^r Hooker⁴ called the later subequal to the terminal ones— The relation is very variable—

2   D-gyroides⁵ sometimes nearly subequal—see plan⁶

3   None have tendrils; no evidence of any being climbers—

Second Letter⁷

District makes no difference in the relation of lat. to term in D. gyrans— There were very small points to some leaves in some species but not anything but what is found in many leguminosæ—(D^r H)

The little leaflets appear very fugacious⁸ in D. Gyrans being often broken off—D^r H believes one must have dropped off in the ones you looked at— The leaflets are opposite.