680 Wisconsin Academy of Sciences, Arts, and Letters. 
Layer c } which takes a dark blue color in iodine, becomes 
pale blue when alcohol is used. The washing out of the 
iodine by alcohol causes a slight shrinkage in the grain, most 
noticeable at the hilum. If now this same grain is kept under 
observation and stained by gentian violet followed by orange 
G, some further interesting data are obtained. Here again the 
stains are applied at one edge of the cover and drawn through 
by means of filter paper. The gentian violet is allowed to re¬ 
main five minutes; it is then washed out by water, and orange 
G is applied and allowed to remain three minutes. This is 
washed out by absolute alcohol, and the preparation is cleared 
by clove oil. During the time of this process there is no change 
in the position of the grain, and a third drawing was made 
of the same portion of the grain showing the appearance of 
the strata when stained by the gentian violet and orange. 
(Dig. 42 C). Around the entire periphery of the grain there 
appears an orange layer (cb). This corresponds approximate¬ 
ly with the pale blue layer a? of the grain stained with iodine. 
The next layer a“ is pale blue and! corresponds with a“. Follow¬ 
ing this layer there is a thin pale blue layer. This is layer 1 
of the grain treated with iodine. The pale blue layer b of the 
grain stained with iodine is split up into two layers, V, a dark 
blue layer, and b“, paler in color, in the grain stained with 
gentian violet. 
The dark line 2 appears as a narrow, very pale blue layer. 
The dark blue layer c appears in the same position as the dark 
blue layer c of the grain stained with iodine. 
The results of this staining experiment are summarized in 
the following table: 
Starch grain represented in Plate XL, Figure A2. 
A (In water.) 
i? (In iodine solution.) 
C (In gentian violet and 
orange G.) 
a—refractive layer 
1 — crevice 
6—refractive layer 
2 — dark line 
c—dark, slightly refractive 
layer 
5 a —light blue 
? «”—dark blue 
1— dark line 
b —pale blue layer 
2 — dark line 
c—dark blue layer 
j o’—orange 
| a”—light blue 
1 — narrow blue layer 
j b ’—dark blue layer 
1 &”—light blue layer 
2 — narrow light blue layer 
c —dark blue layer 
