110 _ BOTANICAL GAZETTE [AUGUST 
of the inflorescence axis; ca, carpels; ce, cutinized epidermis; cw, wall of 
carpels; d, definitive nucleus; dp, degenerating polar nuclei; e, egg nucleus; 
ea, nuclei of egg apparatus; em, embryo; en, endosperm; /, young flower or 
floral apex; fn, fusion nucleus; i, rudimentary integuments; m, mamelon; 
n, nucellus; ~, polar nuclei; pc, fleshy pericarp; p/, placenta; i, pistil; r, 
remains of nuclei of egg apparatus; s,stem; se, sepal; sm, synergid; st, starch; 
v, vascular bundle; 2, very young flower; x, nuclei from which nuclei of egg 
apparatus and polar nuclei are derived; yy, chromatin-like bodies. 
IGS. 1, 7, 8, 12a, 20, and 21 are text figures. 
Fic. 2.—Part of longitudinal section of apex of young spike; X 100. 
Fic. 3.—Lateral view of young spike; Xr. 5. 
Fic. 4.—Part of longitudinal section of apex of spike showing very young 
flower; X 26. 
Fic. 5.—Part of cross-section of young spike showing initiation of flower 
from periblem; X 100. 
Fic. 6.—Lateral view of large spike showing sequence of development of 
flowers; Xr. 5. 
Fic. 9.—Outline of cross-section of -spike showing sunken flower before 
sepals have begun to form; X 26. 
Fic. ro.—Outline of cross-section of spike showing sunken flowers with 
sepals; X 26. 
Fic. 11.—Longitudinal section of flower showing sepals and incipient 
carpels (ca); X26. 
Fic. 12.—Longitudinal section of terminal portion of inflorescence axis 
showing young flowers; X to. 
1G. 13.—Outline of longitudinal section of flower at two-nucleate stage 
of embryo sac; X26. 
1G. 14.—Transverse section of “mamelon” at two-nucleate stage of 
embryo sac; X roo. 
Fic. 15.—Outline of longitudinal section perpendicular to broad surface 
of “mamelon” at two-nucleate stage of embryo sac; X too. 
__¥IG. 16.—Section of part of “mamelon” showing megaspore mother cell 
with subjacent cells (nm) which give rise to nucellar tissue; 150. 
1G. 17.—Longitudinal section of “mamelon” in plane of flattening, 
showing two-nucleate sac, nucellar tissue, and placenta; > 150. 
1G. 18.—Longitudinal section of “mamelon” of D. gracile in plane of 
» Showing uninucleate embryo sac and rudimentary integuments 
oO. 
x -—Portion of section of tracheid tissue at base of “mamelon”; 
250. 
Fis. 22.—Longitudinal section of ripe berry showing embryo, endosperm, 
pericarp, and vascular system: ic, 0, t, tp, as in fig. 21; 1.75. 
Ke 23.—Section of “mamelon”’ showing archesporial cells; X 100. 
IG. 24.—Part of section of “mamelon,” showing megaspores; 150. 

