Volume 1, Issue 8
February 1935, pages 405-470
pp 405-413 February 1935
pp 414-422 February 1935
pp 423-434 February 1935
The inflorescence is divisible into three regions, the lower of completely sterile flowers, the upper of fertile and bisexual flowers and a small middle region with flowers showing an intermediate structure.
The archesporial cells in the anther are rather late in differentiation. The parietal tissue is composed of an endothecium, two middle layers and a uni-nucleate tapetum.
The divisions of the microspore mother cells are simultaneous. Cytokinesis occurs by vacuolation and furrowing.
The pollen grains are shed at the bi-celled stage.
In the young ovule there is usually a single hypodermal archesporial cell, but occasionally two may appear.
The primary parietal cell and also the epidermal cells undergo divisions, so that the mother cell comes to lie 3 to 5 layers deep in the tissue of the nucellus.
A linear tetrad of four megaspores is produced, of which the chalazal functions.
The mature embryo sac is of the usual 8-nucleate type. The synergids and antipodals are ephemeral. The fusion of the polar nuclei seems to be delayed till the time of fertilisation.
pp 435-451 February 1935
pp 452-470 February 1935