172 BOTANICAL GAZETTE [MARCH 
tinues growth and gradually incloses the fertilized egg, in most cases 
forming quite an elongated beak above the embryo. Later many 
of these cells round off, forming a loose tissue, and it is among these 
rounded-off cells that the feeble accessory embryos are produced. 
Whether these have been developed apogamously from the endosperm 
cells, or have budded from the suspensor cells can only be conjectured. 
In any event, they might develop further if there was any failure in 
the development of the normal embryo. 
The time involved in the series described above, that is from the 
first appearance of the megasporangiate strobilus to the maturity of 
the seed, is about thirty months, distributed as follows: June (*); 
first appearance of the strobilus; April, mother-cells in synapsis; 
August, fertilization; October, proembryo of 12 to 18 cells (winter 
condition) ; following season, development of embryo, “rumination” 
of endosperm, and development of testa; October, fall of seed. 
MATURING OF SEED. 
The outer integument and its histological continuation about the 
ovule develops a thick fleshy coat containing very numerous large 
resin cavities, and completely inclosing the structures within (figs. 
4and 5). This fleshy coat gives to the mature seed the appearance 
of a plum (fig. 3), as in the seeds of Cycads and Ginkgo. Within 
the broad band of resin cavities, near the inner limit of the integu- 
ment, two conspicuous vascular strands occur, directly opposite one 
another (fig. 4). These are the main strands of the very charactet- 
istic vascular system of the ovule described by OLIVER (7)- 
The inner integument early differentiates into two distinct layers, 
a differentiation just as evident in Cycads and Ginkgo. The outer 
layer forms the stony coat, and the transformation from soft to very 
hard tissue begins after the embryo and endosperm have completed 
their development. The hardening begins at the apex of the ovule, 
and on account of resistance to stains appears under low power as 4 
clear band (black in fig. 5). The hardening band gradually extends 
downwards through the relatively very short integument, and differ- 
entiating as a distinct layer in the much larger mass of tissue below 
completely invests the ovule within the fleshy coat. Protoplasmic 
connections between the cells of the stony coat and striations in the 
‘ cell walls are unusually clear. 
