LIST OF PLATES. xi 



PLATE III. 



Figs. 17. A barley plant. — 18. Part of same divided down the centre, showing 

 the size and position of inflorescence. — 19. The same, showing the 

 divisions of the inflorescence into undeveloped and developing por- 

 tions. — 20. Inflorescence in a very rudimentary condition. — 21. 

 Further development of same into lobed masses. — 22. More advanced 

 inflorescence. — 23. One of the lobes developed into a perfect flower. — 

 24. Ovary and one stamen separated. 



PLATE IV. 



Figs. 25. A vertical section of mature barley straw. — 26. A portion of silicated 

 epidermis or skin from mature stem, showing the curved prickly hairs. 

 —17. A portion of the epidermis of a leaf without hairs. — 28. A 

 minute portion of a very young awn, with spiral vessels and young 

 hairs developing. — 29. A diagram showing the position of the inflores- 

 cence relatively to the surrounding leaves. — 30. Portion of barley ear 

 showing the lateral supports by which each grain is protected. — 31, 

 Pollen granules. 



PLATE V. 



Figs. 1. A grain of barley. — 2. Another (damaged) gi-ain. — 3. Another (perfect) 

 grain. — 4. The needle. — 5. Hard silicated hairs from its borders. — 

 6. The tuft removed from base of grain. — 7. The position of the tuft 

 relatively to the embryo when the gi-ain is cut across. — 8. A minute 

 portion of wing of tuft, showing the cellular tissue to which the long 

 delicate filaments are attached. — 9. Section of seed through the 

 embryo. — 10. Horizontal section of upper or leaf portion of embryo. 

 — 11. Ditto, of portion forming rootlets. — 12. Starch granules from 

 albumen of seed. 



PLATE VI. 



Figs. 13. Seed coats of barley seeds. — 14. Silica plates on outer layer of cells of 

 skin when dry. — 15. The same after the grain has been steeped in 

 water for some time. — A strobile or fruit of the Hop. — 17. A bract of 

 same, showing the position of: 18. The seed at its base. — 19. Seed 

 with investing membrane to show the liqndite, very abundant on this 

 membrane. — 20, 21. — Seed divested of membrane viewed in face and 

 on edge. — 22. A granule of luptditc burst with dilute sulphuric acid. 

 — 23. A portion of a fruit of brewer's spent-iiops, showing the 

 position of the seeds and lupulite grains unafi"ected by boiling. 

 — 24. A minute portion of the seed peUicle or base of bract (17), 

 beset with lupulite. 



PLATE VII. 



Figs. 1. A grain of Cocculus Indicus. — 2. A diagram of the seed constructed 

 from dissections. — 3. A grain of Paradise. — 4. A diagram of the 

 seed. — 5. Oil globules from the large cysts. — 6. A grain of Datura 

 Stramonium. — 7. A horizontal diagi-am of the seed. 



