PLATE VI. 



FIG. 



13. Seed coats of barley seeds, a, the outer one formed of three 



layers of cells : i. the tabular silicated cells of the epiderm ; 

 2. the elongated fibrous cells underlying these; 3. the tabufer 

 thick-walled cells lying across and under these, b^ the inner 

 coat, consisting of, 4. a delicate pellicle formed of long very 

 thin-walled cells, overlying four or five rows of cells ; 5. with 

 thick walls containing brown colouring matter. 6. c, large 

 albumen cells loaded with starch granules. 



14. Silica plates on outer layer of cells of skin when dry, highly 



magnified. 



15. The same after the grain has been steeped in water for some 



time. The dark lines show the separation of the plates owing 

 to the distension of the grain. 



16. A strobile or fruit of the Hop, n. s. 



17. A bract of same highly magnified, showing the position of — 



18. The seed at its base, n. s. 



19. Seed with investing membrane highly magnified to show the 



lupuUte, very abundant on this membrane. 



20. 21. Seed divested of membrane viewed in face and on edge. 



22. A granule of lupidite burst with dilute sulphuric acid. 



23. A portion of a fruit of brewer's spent-hops, showing the position 



of the seeds and lupulite grains unaffected by boiling. 



24. A minute portion of the seed pellicle or base of bract (17), beset 



with lupulite : s v, spiral vessels and fibre ; /i, hairs ; c, cellular 

 tissue in layer, largely magnified. 



