g2 BOTANICAL GAZETTE [avert 
can scarcely be distinguished from differentiated granular region © 
of the cytoplasm. Indeed, the first clear proof of its preset” 
in my preparations has been the sharp staining of the starch 
grains (purple with gentian violet) that are found almost imme: | 
diately in the interior. The reader may see in fig. 3 such at | 
early stage in the development of the chloroplast, and shouli | 
notice that the three small starch grains lie in a homogene 
matrix of much the same consistency as the surrounding cyte | 
plasm. The chloroplast in cells younger than that shownil 
fig. 3 could not be recognized with certainty by the methods 
staining employed in the present study. - 
The chloroplast once differentiated soon becomes the mo | 
conspicuous object in the spore-mother-cell by virtue of itso | 
and brilliant differentiation with stains (figs. 4, 5) pect 
arities become more apparent as it enlarges. The outline» | 
sharply marked but it has been impossible to establish a distin® 
bounding membrane. The interior contains beautifully define! 
starch grains that become very numerous as the chloropl# 
increases in size and finally fill by far the greater part of th 
enclosed region. Each starch grain at first occupies @ 1 
cavity surrounded by delicate films of protoplasm that app™ 
as strands in the sections figured (figs. 5-9). The chlorop 
has therefore a honeycomb-like structure, each cavity Dem 
chloroplast where they merge into the densely staining fil 
the exterior. But the bounding film grades off insensibly ™ 
the cytoplasm and it was not possible to distinguish by 4%) 
reaction the strands inside the chloroplast from the protel 
outside. 
The first division of the chloroplast takes place very ee 
after the structure reaches a certain size. Preparation ae 
process is usually indicated by the chloroplast elongatit 
bending around the nucleus in the form of a thick cr 
