[320]

Bean

(Part. above pencil line to be engraved on 2/3 scale. 5 4 sets of lettering)

F 130.

[321]

Vicia faba circumnutation of leaf       

Vicia faba: circumnutation of whole leaf, traced from 7° 15 P.m on July 2' to 10. 15 a m 4th. Apex of leaflet 7 1/4 from vertical glass ─Tracing here reduced to 2.3 of origin scale.

Temp. 17°–18° C.

[321v]

696 85

Chapter E 10

cross-fertilisation, being subsequently much increased in quantity and stored in various ways. This view is rendered probable by the leaves of some trees excreting, under certain climatic conditions a saccharine fluid, often called honey-dew, without the aid of special glands. This is the case with the leaves of the lime; for although some authors have disputed the fact, a most capable judge, and Dr. Maxwell Masters, informs me that after having heard the discussions on this subject before the Horticultural Society, he has feels no doubt on this head. although others have doubted. The leaves, as well as the cut stems, of the B mauna ash (Fraxinus ornus) secrete in a like manner saccharine fluid matter.* (*Gard. Chron. 1876. p. 242). According to an excellent observer Treviranus, this is likewise the case during hot weather with the upper surfaces of the leaves of Carduus arctioides. Many analogous facts could be given.*(5) (*Kurr,, Untersuche ungen über die Bedeutung der Nektarien. 1833 p. 115). There are, however, a considerable number of plants,*(6) which bear small