1912] PACE—PARNASSIA 313 



inner row of cells of the integument next to this part of the sac is 

 disintegrating, the disorganization being more or less complete as 

 far down as the last cell drawn, which seems to be still active, as 

 both nucleus and cytoplasm have the usual staining reaction and 

 structure of active cells. Fig. 43 is the other view of a similar sac, 

 being cut at right angles to that of fig. 42; the other synergid is 

 directly under the one drawn. Here the egg apparatus is farther 

 up in the micropyle, and a few of the cells of the integument over 

 the filiform cap have entirely disappeared. Chodat (3) shows an 

 embryo sac before and after fusion of the polars in his figs. 664 and 

 665, but does not show the filiform apparatus of the synergids. 

 His fig. 677 suggests the possibility of its presence, but does not show 

 it clearly. The pollen tube is just below it. 



In many ovules the egg apparatus is entirely in the micropyle, 

 a few of the cells of the integument being disorganized in most 

 instances (fig. 44). The whole egg apparatus has the appearance of 

 being squeezed into a space too small for it. The polars have fused. 

 In fig. 45 the synergids lie one above the other in the micropyle, the 

 egg being just at its entrance. These synergids show the notch and 

 the filiform appearance quite distinctly. If the synergids are not 

 entirely separated, they may have somewhat the appearance of 

 pollen tubes; but it is always easy to distinguish them from the 

 latter by the difference in staining reaction, and by the fact that the 

 real tube structure is lacking. A diagram with less magnification 

 (fig. 46) shows the whole upper portion of the ovule. Fig. 47 shows 

 one synergid nucleus just at the entrance of the micropyle, some of 

 the cytoplasm of this synergid being entirely outside of the ovule. 

 In fig. 48 the entire egg apparatus is just at the entrance to the 

 micropyle, with the polars in contact in the upper part of the sac. 

 A few ovules were seen in which the whole of the egg apparatus was 

 entirely outside of the micropyle. These figures with the synergids 

 in the micropyle are very similar to the structures shown by Chodat 

 (3) in his figs. 675-676, which he calls pollen tubes. 



Pollen.— The anthers present the usual four-lobed appearance, 

 with four sporogenous regions. A group of mother cells in more or 

 less perfect synapsis is shown in fig. 49. After synapsis there is a 

 thick spirem which segments into 10 chromosomes (fig. 50). The 



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