1915] HUTCHINSON—MALE GAMETOPHYTE OF PICEA 293 
to osmosis. Moreover, the increase in size is most rapid when the 
nucleus is surrounded by most cytoplasm; the primary nucleus 
soon regains the size characteristic of the resting stage (figs. 6, 9, 
£o) 20, 91). 
Chromatic structures 
The resting nucleus contains several nucleoli. In early pro- 
phase “condensing bands” and “zig-zag threads’? of chromatin 
become differentiated; definite looped chromosomes are formed 
(figs. 15, 35). Only in rare cases could their double nature be seen 
at this stage; it would seem that the halves remain rather closely 
appressed until metaphase. The nucleoli are present until late 
prophase (figs. 16, 35, 48). The chromosomes contract before 
aggregating in a definite cell plate (figs. 16, 48); during anaphase 
they are characteristically V-shaped (figs. 2, 3, 17). In early 
telophase compact chromatic aggregations are formed (figs. 4, 18, 
41, 47, 49). These soon become irregularly vacuolate, and as the 
vacuoles increase in size, anastomosed bands of chromatin become 
differentiated (figs. s, 22, 24, 43). The process is similar to that 
described by SHarp (8) in Vicia. The bands become more irregular 
in outline, and a number of nucleoli appear (figs. 23, 25, 44). As 
the number of nucleoli decreases, they become individually larger 
(figs. 20, 45, 6, 8, 46, 48, 50). The irregular bands are replaced 
by zig-zag threads and the nucleus passes again into the resting 
condition. 
Achromatic structures 
The achromatic structures in all primary divisions are most 
characteristic. The spindle fibers are inconspicuous during ana- 
Phase (figs. 2, 3, 36, 42); in many cases they can be distinguished 
only with difficulty (fig. 17) and are only slightly more definite 
than the vague radiations in the polar cytoplasm (figs. 3, 36).. In 
early telophase there are very definite strands between the daughter 
nuclei. These are arranged in the form of a hollow cylinder (figs. 
4, 18) which gradually broadens (figs. 19, 43) and moves toward 
the pole, partly enclosing the antheridial nucleus (figs. 5, 21, 24). 
Usually the fibers come in contact with the cell wall, the free 
ends swing outward, and so remain as curved or radiating strands 
