1913] PACE—APOGAMY IN ATAMOSCO 383 
nuclei unless the egg apparatus approaches that region. Fig. 32 is 
from a sac with 13 nuclei, 7 of which have the organization of the 
antipodals at the micropylar end of the sac, 4 are in the lower part 
of the sac near the antipodal region, two synergids and two eggs, 
while the two polars are the only normal feature of the sac. The 
pollen tube is entering the egg apparatus. 
As was said above, in the large majority of these abnormal sacs 
there are the usual 8 nuclei, and these have the usual organization, 
but the groups are not in the usual position. Fig. 33 shows a 
common arrangement except the antipodals here are not exactly at 
the micropylar end. The egg apparatus is perfect (fig. 33, a), as are 
the polars and antipodals, each group showing its characteristic 
differentiation. A four-celled embryo in a similar sac is shown in 
fig. 34. Here the primary endosperm has not divided. Porscx 
(21) and those holding the archegonium theory would regard these 
extra groups as the organization of additional archegonia. If the 
two groups of cells usually found in an embryo sac are archegonia, 
the interchange of characteristic organization would not be very 
remarkable. In the 16-nucleate sac of Euphorbia procera, Movt- 
LEWSKI (15) figures 4 groups of 4 nuclei each. From each of these 
groups one nucleus moves to the center to form the primary 
endosperm nucleus, leaving 3 in each of the groups. The micro- 
pylar group he calls the egg apparatus, and that one is the only one 
figured as functioning. But each of the groups at the side of the 
sac have the appearance of an egg apparatus. 
Discussion 
The egg apparatus is almost diagrammatic, so the first thing to 
attract attention was the very small sperm nucleus as compared with 
the egg nucleus. But as the egg nucleus contains very little stain- 
able material except the nucleolus, while the sperm nucleus is very 
dense, the real condition was not suspected, for the sperm nucleus 
is often much smaller than the egg nucleus. Lanp (14) figures a 
very small but dense spiral sperm in Silphium. NAWASCHIN (17) 
shows a similar one in Helianthus. GUIGNARD gives a like condition 
in Iris (7), and in some of the Ranunculaceae (9) and Solanaceae 
