14 Humphrey . — The Development of the 
is a rare phenomenon, and suggests interesting physiological 
inquiries as to its significance. A priori it is not easy to see 
what special need of this particular seed should have led 
to the development or preservation of these structures in so 
unusual a place. So far as one can judge from their structure 
and that of surrounding cells, they can hardly remain func- 
tional much later than the time when the seed reaches about 
half of its adult length. Schleiden and Vogel (’42), Haber- 
landt(’84), and Overhage (’87) have suggested that these open 
pores furnish the only means for the penetration of water 
into the seed at the beginning of germination. Against this 
idea it may be urged that they are completely closed below 
by the sclerotic layer of the testa, beneath which is the dense 
nutrient layer : and further, the equally dense coats of other 
seeds have no stomata. It is much more probable that water 
can penetrate into the seed of Canna through the germinal slit. 
The chalazal perisperm lying between the testa and the 
embryo-sac becomes, like the perisperm of other seeds, 
a storage-tissue. The perisperm-cells become gradually 
elongated in a radial direction, beginning with those which 
border on the embryonal cavity ; and soon starch is deposited 
in characteristic grains in them, until all are filled, those next 
to the testa last. Concomitantly with the deposition of 
starch in the cells, their walls become slightly thickened and 
pitted. So completely are the cells filled with starch that 
the impressions of the grains upon the walls are very evident 
after their emptying during germination (psp., Fig. 24). 
We have now to notice the two tissues developing within 
the embryo-sac. The fertilized egg-cell develops directly 
into the embryo without the formation of a suspensor, Hof- 
meister’s statements to the contrary notwithstanding. Details 
of its development were not followed out, since they have 
been sufficiently described by Hegelmaier (’74). The adult 
embryo is remarkable for the high degree of differentiation 
which it reaches, especially in its plumule and in the number 
of accessory root-rudiments. When germination begins, the 
elongation of the neck of the absorbing organ pushes out the 
