356 Mot tier. — On Certain P/asiids, with Special Reference to 
we have generally one large rounded and densely staining body to the 
vacuole. It frequently happens (Fig. 10) that these large bodies do not 
lie in a vacuole, while in the same cell the vacuole is conspicuous and much 
larger than the contained protein mass. In the intercellular spaces, and 
in the space left in the corners of cells in which some shrinkage has taken 
place, a homogeneous substance, somewhat brownish in colour, is seen, which 
in all probability consists of the remains of the oil that was not removed 
by the alcohol and other reagents used in the processes of embedding and 
staining (Fig. 10, x). Sometimes a portion of this substance finds its way 
into the cavity surrounding the protein mass. In the more mature cells 
of the seed the large protein mass (Fig. 9 f ) gives evidence of becoming 
angular, and a rounded body is near by, which is doubtless the globoid. 
Fig. 9 f and Fig. 10 were taken from the same section. Angular bodies 
were not found in the younger stages of development. In endosperm cells 
of the mature and dry seeds, prepared by fixing and staining, little remains 
save the angular crystalloids and fragments of the membrane of the aleurone 
grain. In preparing the endosperm of the dry seed for sectioning and 
staining, it was necessary to cut it up into small pieces, and, as castor oil 
is miscible in absolute alcohol, it is not to be expected that any oil would 
remain in the cells. 
The facts brought out in this study seem to point to the conclusion 
that the aleurone grains in Ricinus have their origin in small granular 
primordia existing in the cytoplasm. Such primordia increase in size and 
collect in large numbers in vacuole-like cavities. Later they or their 
generated products fuse to form one or more large masses which, during 
the final steps in the maturing of the seed, take the form of the well-known 
crystalloid near which is often found the globoid. The amorphous protein 
which surrounds the crystalloid of the mature seed, and which is brought 
into evidence by treating sections of mature endosperm with absolute 
alcohol followed by iodine, is not to be demonstrated, either in any stage 
of development as here observed, or in the mature endosperm. There is 
a possibility that the amorphous protein so called is not real protein, or it 
is of such a nature as not to be rendered visible by the fixing and staining 
employed. 
There is nothing in the process of development observed here that 
lends support to the view expressed by Pfeffer that a globoid is the starting- 
point about which an aleurone granule is formed. Wakker calls attention 
to small bodies in the centre of the vacuole which shows molecular 
movements, and which represent the beginning of the future crystalloids. 
He leaves the impression that each body in the vacuole becomes a crystalloid. 
He does not mention any fusion of the bodies, and his figures do not help ' 
to make the text clearer on this point. As a matter of fact the bodies 
shown in Figs. 7-9, are so numerous that the conclusion that they unite 
to form larger masses is imperative. 
