24 
EXPLANATION OF PLATES. 
Figs. 1-4. Phaseolus vulgaris. 
Fig. 1. Surface view of palisade cell; x 700. 
Fig. 2. Cross section of seed-coat; x 120. I. Palisade 
layer; a, narrow light line. II. Crystal layer. III. Layer of 
simple parenchyma. IV. Layer of parenchyma, containing 
fibro-vascular elements. V. Layer of compact, branched cells. 
VI. Aleurone layer. VII. Starch layer. 
Figs. 3-4. Isolated’ palisade cells, macerated in potash; x 25 
Figs. 5-11. Gymnocladus Canadensis. 
Fig. 5. Cross section of bean; natural size. 
Fig. 6. Surface view of palisade cell; x 700. 
Fig. 7. Cross section of the seed-coat; x 120. I. Palisade — 
layer; @, cuticle; 6, wide light line; c, refractive points; a, ; 
narrow light line. II. I-shaped support-cells. III. Sclerenchy 
cells. IV. Pigment layer. V. Layer of thick-walled parenchy1 
and spiral vessels. VI. Layer of star-shaped parenchyma cell 
J, upper portion ; g,lower portion. VII. Aleurone layer. 
Figs. 8, 9 and 10. Isolated palisade cells, macerated in potas 
x 175; 4, refractive points. 
Fig. 11. Cells of upper portion of VI. layer; x 350. 
Figs. 12-16. Physostigma venenosum. 
Figs. 12 and 13. Surface view of palisade cells; x 700. 
Figs. 14 and 15. Isolated palisade cells, macerated in potasl 
x 175. 
Fig. 16. Cross section of seed-coat ; x 120. I. Palisade la 
a, cuticle; 0, light line. II. I-shaped cells. III. Loose, 
walled parenchyma. IV. Pigment layer. 
Figs. 17-21. Wucuna urens. 
Fig. 17. Surface view of palisade cell; x 700. 
Fig. 18. Cross section of seed-coat; Xx 120. 
layer; a, cuticle; 0, lightline. II. ¢ is the homo 
shaped support-cells in Gymmnocladus Canaden. 
crystal layer in Phaseolus vulgaris. 11. Aleurone layer. 
Figs. 19, 20 and 21. Isolated palisade cells, macerated in 
potash; x 175. 
