530 Wisconsin Academy of Sciences , Arts, and Letters. 
small grains are found as small round orange colored bodies, 
and are always surrounded at this stage by a large leucoplast. 
Certain of these young grains show no signs of lamination, 
others no larger in size show one or two pale violet circles 
toward the center but no violet layers. Still other grains show 
a pale violet region at the center around the dark violet hilum. 
Grains in the same region and slightly larger show a central 
region stained dark violet, surrounded by a pale violet layer 
and this, surrounded by an orange layer. Preparations of this 
kind show that the violet layers at the center are the first to be 
formed. 
As an eccentric grain grows the plastid becomes stretched 
and the mass of it remains at one end of the grain. It is be¬ 
neath this mass of the leucoplast that the broader portions of the 
eccentric layers are deposited. The orange layer is usually of 
fairly uniform width around the grain. In some cases where 
the orange layer was not found, the grains showed evidences of 
solution on the outside. 
The starch of a number of other plants was examined and 
with similar staining the orange layer found to be, present. 
In barley and wheat the starch grains are concentric and in both 
we find an orange layer at the outside. In the leaves and stems 
of Pellonia Daveauana large eccentric starch grains are present 
which show the orange staining layer beneath the chloroplast. 
In starch from Dieffenbaehia Seguina , Phajus grandifolius 
Oxalis viola and Bicentra cueullaria, orange staining outer lay¬ 
ers are found. 
This constancy of the orange layer, occurring as it does, from 
the very young to the very old grains, seems to point to the fact 
that we have in the starch grain two substances, differing in 
their properties, one staining violet and the other orange. One 
striking fact noted was that while the outer orange staining 
layer completely surrounded the grain, the violet layer next to 
it runs only part way around. If the outer layer is simply 
denser starch, as is claimed by Salter, it is difficult to account 
for the formation of eccentric layers of starch inside the so- 
called dense layer. 
The following experiment gives strong evidence that the vio¬ 
let stain passes through the orange layer readily but is not 
absorbed by it. In microtome sections, the staining of a large 
eccentric Ganna grain may be watched under the microscope 
