1913] PACE—APOGAMY IN ATAMOSCO 377 
part of 10 per cent formalin) were also used. The triple stain, 
safranin, gentian violet, and orange G, and iron hematoxylon were 
found most satisfactory. 
Pollen 
The pollen is quite normal in every way in the anthers sectioned 
(fig. 1). The tube nucleus is usually somewhat amoeboid in shape 
and occasionally has more than one nucleolus. The generative cell 
with its nucleus and bit of cytoplasm about it is quite small. In 
this figure the generative nucleus has the chromosomes segmented. 
The number is 12 and was counted in several other grains in the 
same anther. But in the majority of the pollen grains studied the 
generative nucleus was in the spirem stage (fig. 2). In this same 
anther a few grains were seen with possibly two generative a 
but it is propable they are the sperm nuclei, as they are both in 
same cell. A‘ germinating pollen grain from the stigma shows the 
generative nucleus in mitosis and in advance of the tube nucleus 
(fig. 3). In fig. 3, a this nucleus is shown with greater magnification, 
and the remainder of this nucleus, which was in the adjacent section, 
is shown in b. The chromosomes show longitudinal splitting and 
there are 12. 
Embryo sac 
The mother cell.is only slightly larger than the adjacent cells 
when first distinguishable (fig. 4). ‘The ovule now increases rapidly 
in size and the mother cell becomes very large. The division of the 
mother cell has not been seen. Many ovaries with ovules showing 
large mother cells have been cut, and many that were apparently 
the same size had mature sacs. The development of the sac must 
be very rapid, for several ovaries had mature sacs and mother cells 
apparently occurring together without any definite order. But 
other ovaries showed all ovules in the same stage of development; 
one in particular has every ovule with the nuclei of its sac in the 
third and last division, with all stages of mitosis from well developed 
spirem to late telophase. 
The two-nucleate (fig. 5) and four-nucleate sacs show nothing 
unusual. The spirem for the next division has the normal appear- 
ance. In figs. 6 and 6, a the anaphase stage of the two nuclei from 
