172 | BOTANICAL GAZETTE [FEBRUARY 
Fics. 17, 18.—Lamellate plugs; 67 
Fic. t9.—An unusual form of fits plug from thé race on Spilanthes; 
X 670. 
Fic. 20.—A bell-shaped plug, apparently secondarily filled up; 670. 
Fic. 21.—A bell-shaped plug which is perforate; 670. 
Fic. 22.—A binucleate cyst with part of its rhizoids showing by a starch- 
free area the approximate size and position of the primary nucleus and the 
remains of the residual chromatin cast out during the primary mitosis; 334. 
Fic. 23.—The tetranucleate stage; drawn from two sections of a retort- 
shaped cyst with the bend perpendicular to the plane of section; the spo- 
rangium, and especially the vacuole, were therefore larger than is indicated in 
the drawing; 334. 
Fic. 24.—An 8-nucleate cyst in which the position of the primary nucleus 
is still clearly indicated by a starch-free area in the cytoplasm; only six nuclei 
in plane of section; 334. 
Fic. 25.—An oblique section of 16-nucleate cyst in which the nuclei were 
still bunched in the center; XX 334. 
Fic. 26.—A small cyst in the 32-nucleate stage; 334. 
Fic. 27.—A cyst with about 128 nuclei; XX 334. 
Fic. 28.—A segmented zoosporangium, the ae er retaining the 
shape of the coenocyte from which they were derived; 
Fic. 29.—A cyst apparently segmenting by cleavage eek: $; X1000 
Fic. 30.—Preliminary contraction resulting in pseudo-segmentation during 
the last mitoses; 1000 
1G. 31.—Segmentation by the precipitation of membranes in the cyto- 
plasm: a, a wall just forming; 6, a portion of cytoplasm left out between the 
segments; X 1000 
Fic. 32.—A newly formed protospore; 2000 
Fic. 33.—A protospore rounded off and cvihiing to show the concentra- 
tion of the chromatin; XX 2000 
1G. 34.—A protospore ceebilanued: showing the body at the base of the 
cilia and oe connection with the nucleus; X 2000. 
. 35.—A young spore with starch grains partly concentrated in the 
posterior end; chromatin concentrated into a single mass; X 2000 
Fic. 36.—Mature spore from a section showing basal body wil antero- 
posterior differentiation of the spore; X 2000. 
Fic. 37.—Free swimming zoospore killed with osmic fumes stained with 
ere en X 1000. 
—41.—Stages in the conjugation of the zoospores from living 
ideo “cilia diagrammatic; the difference in size between the gametes was 
acci sti there is no differentiation into microgametes and megagametes. 
. 42.—A nucleus from a very young cyst; > 2000 
Fic 1G. 43.—A nucleus from a young resting spore; vacuolation of karyosome 
beginning; few connections between the chromatin spherul es; 2000. 
