Denniston—Growth and Organization of the Starch Grain. 693' 
Still other grains show a pale violet region at the center 
(Fig. 9). Slightly larger grains show a central dark violet re¬ 
gion, surrounded by a pale violet layer, and this in turn by an 
orange-stained peripheral layer (Fig. 5). The early violet 
layers appear to he made up of starch substance distinct from 
the orange-staining material of which the young grain is com¬ 
posed. As the grain enlarges, more violet layers form and the 
orange peripheral layer retains a -fairly uniform thickness 
around the grain (Figs. 10-12, 34). 
Frequently young grains of Ganna appear which are stained 
entirely orange with the exception of one or two minute dots 
(Fig. 16). These dots are no doubt the beginnings of regions 
which will later take the violet stain. A grain in a neighbor¬ 
ing cell (Fig. 15) is enclosed by a plastid. The grain is 
stained orange, but with a small violekstained region at the 
center which is evidently made up of two parts, each with its 
own hilum. 
A small grain which has an eccentric position in the leuco- 
plast, but which has not as yet any eccentric layers, is often 
present (Fig. 13). A concentric grain of C'anna often shows a 
thin leucoplast, a broad orange layer and a pale violet central 
region (Fig. 14). 
In many large grains the leucoplast can be traced entirely 
around the periphery (Fig. 33) ; in others (Fig 31) but a 
remnant of it remains. 
Certain grains show the effects of solution in the plastid 
and subsequent growth, with a shifting of the plastid (Fig. 32). 
The layers in the corroded portion show the effect of corrosion 
most strongly at the posterior end of that portion of the grain. 
With a period of renewed growth, the plastid shifts its position 
and the new layers are put down at an angle of about 45° to 
the old. Probably the plastid remains as a membrane around 
the grain, but the layers appear to be deposited only where the 
plastid is thickest. 
In the concentric starch grains found in the seed of Goix 
lachryma, the small grains stain completely orange and show 
the plastid as a layer of uniform width at the periphery; 
