ON THE RELATIONSHIP BETWEEN THE LENGTH OF 
THE POD AND FERTILITY AND FECUNDITY 
IN CERCIS 
J. ARTHUR HARRIS 
(WITH ONE FIGURE) 
It is well known to botanists that the egg cell is not the only struc- 
ture affected by fertilization. GOEBEL points out' that in the Hepati- 
cae an accompanying result is often seen in the production of a further 
development of the envelopes of the ripening sporangium. Again, 
in the same work he suggests? that the stimulus exercised by pollina- 
tion in the flowering plants is most probably chemical. The prepara- 
tion of the ovules for fertilization is dependent in some cases upon 
pollination. For instance, in such plants as Corylus, Alnus, Quercus, 
and some of their allies, there is no sign of the placenta in the ovary, 
to say nothing of ovules, at the time of pollination. In most species 
of Orchidaceae the ovules are laid down at the time of pollination, 
but still are rudimentary. The stimulus exercised by the pollen tube 
induces the further development of the female sexual apparatus in 
these plants. 
PFEFFER’ joins with GOEBEL in considering that the penetration 
of the pollen tube may serve as a stimulus to the development of the 
ovary, and cites the seedless fruits studied by Mi1LeR-THURGAU 
and the observations on Ficus by TREUB. 
Jost* writes: “The germination of the pollen tube has an exciting 
influence on the development of the fruit. This is particularly 
noticeable in certain cultivated plants, which, as for example currants 
and sultana raisins, produce no seeds, the ovules having degenerated. 
If the stigmas of these plants be not pollinated, the fruit fails to 
develop, but pollination leads to development without leading to any 
fertilization.” 
* Organography of plants 2:105. 1902. 
? Op. cit. 1:269-270. 1900. 
5 Physiology of plants (English transl.) 2:173. 1900-1906. 
* Lectures on plant physiology (English transl.) p. 370. 1907. 
117] [Botanical Gazette, vol 50. 
