the Protein Bodies of Zea, Ricinus , and Conopholis. 363 
16. Rendle, A. B. (1888/) : On the Development of Aleurone Grains in the Lupin. Ann. Bot., 
vol. ii, pp. 161-7. 
17. Schimper, A. F. W. (1880) : Untersnchungen ii. d. Entstehung der Starkekorner. Bot. Zeit., 
Bd. xxxviii. 
18. de Vries, H. (1910) : Intracellular Pangenesis. English translation, by C. Stuart Gager. 
19. Wakker, J. (1888) : Studien iiber die Inhaltskorper der Pflanzenzelle. Jahrb. f. wiss. Bot., 
Bd. xix, pp. 423-96. 
20. Werminski, F. (1888) : Ueber die 'Nairn r der Aleuronkorner. Ber. der Deutsch. Bot. Gesell., 
Bd. vi, pp. 199-203. 
EXPLANATION OF PLATE XV. 
Illustrating'Professor Mottier’s paper on Certain Plastids, with Special Reference to the 
Protein Bodies of Zea , Ricinus , and Conopholis. 
All figures were drawn from permanent preparations, with the aid of the camera lucida. 
Figs. 1-5. Zea Mays. 
Fig. 1. Starchy corn. A cell from the outermost layer of the young endosperm. The granules 
of varying sizes in the cytoplasm represent the primordia of plastids. x 1,200. 
Fig. 2. Starchy corn. Two cells of the aleurone layer from an older grain of corn with the 
next three cells beneath in a radial direction. The young protein granules, aleurone, are now very 
evident. Among them in the cytoplasm are numerous densely staining granules. In the first two 
cells beneath the aleurone 'layer at this stage few protein granules are present, x 1,200. 
Fig. 3. Golden Bantam. A cell of the aleurone layer, from a much older grain of corn. The 
cell-wall is very thick. Among the very large aleurone granules are many smaller, representing 
a complete gradation to the primordia. x 1,200. 
Fig. 4. Three cells lying in a radial direction beneath Fig. 3. In all three are numerous 
protein granules of a more nearly uniform size. In the first cell no starch grains are present, a few 
appearing in the second ; in the third and larger cell a number of compound starch grains are present 
among the numerous protein granules, x 1,200. 
Fig. 5. Starchy corn. A cell lying deeper in the endosperm, of the same section from which 
Fig. 2 was drawn. The numerous simple starch grains are aggregated about the nucleus. In the 
groundwork of the cytoplasm numerous'’ small and densely staining rods and granules are also 
present, x 1,200. 
Figs. 6-1 1. Ricinus. 
Fig. 6. A cell from the periphery of the endosperm with several vacuoles containing only cell- 
sap. In the cytoplasm are larger rounded bodies and smaller rods and granules, the primordia of 
plastids. x 1,300. 
Figs. 7 and 8. Cells lying deeper in the endosperm. In the centre of each cell lies the nucleus. 
About midway between nucleus and cell-wall are arranged with considerable regularity the vacuole- 
like cavities, in each of which are contained numerous rounded and very densely staining bodies, the 
primordia of the future protein masses or aleurone grains. In the cytoplasm are also rounded 
bodies resembling, leucoplasts, and staining lightly. They may be oil plastids. Among them are 
very small densely staining rods and granules. In Fig. 8 the bodies in the vacuole-like cavities are 
larger. Figs. 7 b, 7 c, two cavities of different size, and containing respectively granules of different 
size, x 1,300. 
Figs. 9 a~gf Successive steps in the formation of a more mature aleurone mass, /was taken 
from the same endosperm as Fig. 10. x 1,300, 
