422 Cutting. — Observations on Variations in the 
beginning of autumn, as a consequence of injury to the apical bud ; in such 
cases, structures that would ordinarily be developed as scale leaves are 
formed into transitional leaves. Such structures, if situated in the anterior- 
posterior plane, have enlarged bases which are quite free ; if, however, they 
are placed right and left of the shoot, the bases are generally fused on the 
side towards the parent shoot, but free on the other side. It is possible 
that some comparable nutritional disturbance is responsible both for the 
fusion between flowers in Siackys, and for the occasional bifurcation of the 
upper lip of the corolla. 
The tendencies to bud-pollination and gynomonoecism were shown only 
in the autumn. The work of Vochting (41, 42) has indicated that in 
Mimulus light is the controlling factor in cleistogamy, and in other plants 
temperature also has been shown to be important ; while Graebner, in 1893 
(19), has expressed the opinion that cleistogamy is brought about by any 
adverse influence, e. g. lowering of temperature, amount of light, or the 
weakening action of fungi. Willis (45-48) is in agreement with this view, 
and also expresses the opinion that the peculiar distributions of the sexes 
seen in the Labiatae and other orders are also expressions of the action of 
external adverse conditions. It is not known precisely what set of external 
conditions favour cleistogamy rather than gynodioecism or androdioecism. 
It is possible that the time of action of the factor relative to the stage of 
development of the plant or flower must be taken into consideration. The 
observations of Delassus (11, 12 ) and of Urbain (39) are here of some im- 
portance, for they have shown that the effects of partial or complete 
removal of the endosperm or of fleshy cotyledons are felt far into the life of 
the plant, influencing the time of flowering, the number of flowers, and in 
some plants producing frequent sexual abnormalities. This fact makes the 
investigation of any such phenomena difficult, for it is not an easy matter to 
trace back any anomaly to its cause, and the case of S tacky s would be 
especially difficult as, when in bloom, it has many flowers in different stages, 
and these flowers react on one another, the development of one flower often 
causing the non-development of another by correlation. 
Klebs’s work on the importance of light in bringing about flower forma- 
tion ( 22), 1 and especially the extension of this view by which it is held that 
an excess of starch-formation is responsible for flowering and an excess of 
salts for vegetative development, impresses on us the presence of quantitative 
factors as apart from qualitative ones. Sprecher’s results on Rumex and 
Ca7inabis (36), in which genera he finds that in the different sexes there are 
different osmotic pressures in the expressed juices and that the mineral and 
organic matters present in the extract are also not the same, point to con- 
clusions similar to those to be drawn from Klebs’s work. It is true that 
several workers have held that the sex in hemp and similar plants is fixed 
1 See also Garner and Allard (14), and Giron de Bazareingues (16). 
