352 BOTANICAL GAZETTE [NOVEMBER 
and globules, so that the periphery of the egg always contains the 
most conspicuous contribution from the jacket. The food materials 
never take the form of “proteid vacuoles” as in Pinus, and are never 
in danger of being mistaken for nuclear structures. The appear- 
ance of the jacket and the periphery after a discharge is almost com- 
pleted is shown in jig. 38. 
The three preceding illustrations (figs. 36-38) show the condi- 
tions in young eggs while the protoplasm is still quite scanty, most 
of the space being occupied by large vacuoles. Later stages, after 
the egg has become filled with protoplasm and the large vacuoles 
have disappeared, are shown in figs. 39-41. In fig. 39 the ends of 
the haustoria are covered by a frothy substance, and in fig. 4o it is 
seen that this substance is passing into the egg. A large vacuole 
marks the place which has just before been occupied by frothy sub- 
stance. The nucleus, as is often the case, is concave on the side 
next the haustoria. A later stage is shown in fig. 41, which repre- 
sents various kinds of food materials within the egg. Globules and 
droplets of various forms are most abundant, but crystalloids are not 
infrequent. The crystalloids are cubical or may approach the 
spherical form, but are never fusiform like those so characteristic 
of the egg of Zamia. Starch is sometimes present but generally 
absent. = } 
The structure of the protoplasm of the egg undergoes great changes, 
especially during the last two months of its development. In Decem- 
ber the protoplasm, containing one large vacuole, forms only a thin 
layer pressed against the periphery of the central cell (jig. 25)- In 
March the protoplasm has increased greatly in quantity and numerous 
vacuoles have appeared (figs. 36-38). In these figures, and even in 
considerably later stages, the lines represent the edges of lamellae, 
and the appearance is a strong argument in favor of the foam or 
Waben theory of the structure of protoplasm. In later stages, 
however, the foam structure disappears, and the protoplasm seems 
to be almost entirely in the form of fibrillae (fig. 41). The change - 
seems due in great part to the breaking down of lamellae, thus leaving 
fibrillae at the junctions. 
Why the nucleus of the central cell remains at the apex for s0 
many months, and why after the mitosis the egg nucleus moves down 
