ON NAIAS GKAMINEA DEL., VAB. DELILEI MAGNUS. 29 



XX. — Explanation oe the Figures 



Plate 249. 

 Fig. 1. The upper portion of a branch of N. graminea, from Reddish ; nat. 

 size. 



2. Two of the leaves from same, drawn rather broader than the natural 



size, the sheaths and auricles flattened out. 



Plate 250. 



3. Upper portion of a branch of N. graminea from Lower Egypt. Copied 



from Delile's drawing in his ' Flore de l'Bgypte,' but reduced to two- 

 thirds original size. 



4. Base of a leaf-fascicle, showing leaf-auricles, fruits, &o. ; slightly 



enlarged. From Delile's 'Flore de l'Egypte.' 



5. Section of fruit ; enlarged. From Delile's ' Flore de l'Egypte.' 



Plate 251. 

 6 — 8. Arrangement of the cells of the marginal spines on the leaf of (6), 



N.flexilis; (7), N. graminea; (8), N. minor and N. arguta. From 



Dr. Alexander Braun's sketches in ' Journal of Botany,' 1864, vol ii., 



p. 275. 

 9. Form of sheath at base of leaf of N. minor; from ' Compendio della 



Flora Italiana,' of Cesati, Passerini, and Gibelli, tav. xxviii, fig. In. 

 10 — 14. Form of sheath at base of leaf of (10), N.flexilis; (11), N. minor; 



(12), N. minor, var. setacea; (13), N. falciculata: and (14), N. 



graminea. All copied from Dr. A. Braun's woodcuts in ' Journal 



of Botany,' 1864, vol. ii., p. 274. • ' 



15. Male flower of N. tenuifolia B. Br. Enlarged y. From Magnus's 



' Beitrage,' plate iv., fig. 5. 



16. Anther of N. major, with the perianth reflexed; enlarged. From 



' Genera Plantarum Flora? Germanics,' Th. Fr. Lud. Nees ab Esen- 

 bedk, Fasc. vi., Naias, fig. 5. 



17. Male flower of N. minor; enlarged. Nees ab Esenbeck, I. c, fig. 24. 



18. Transverse section of male flower of N. major. Nees ab Esenbeck, I.e., 



fig. 7. 



19. Pollen of N. major; enlarged. Nees ab Esenbeck, I. c, fig. 8. 



20. Male flower of N. major, with the perianth drawn back; enlarged. 



From ' Iconographia familiarum naturalium regni vegetabilis,' 

 Dr. Adalbert Schnizlein, Heft v., pi. 71, fig. 4. 



21. Vertical section of male flower of N. major: enlarged. Schnizlein, 



I. c, fig. 6. 



22. Male flower of N. major, showing the separation of the perianth from 



the anther ; enlarged. Schnizlein, I. c. fig. 7. 



23. Vertical section of a male flower of N. major. From ' Compendio della 



Flora Italiana,' I. c, fig. 1 o. 

 24 — 25. Dehiscence of the perianth of N. major, after the observations 

 of Braun ; enlarged. Nees ab Esenbeck, I. c, figs. 9 and 10. 



26. Grains of pollen of N . major, with fovilla ; enlarged 2 ^°. From 



' ' Compend. Fl. It.,' I. c, fig. 1 d. 



27. Vertical section of a male flower of N. minor All. ; enlarged. ' Compend. 



Fl. It.,' I. c, fig. 1 e. 



28. Male flower of N. major ; enlarged $. ' Compend. Fl. It.,' I, c, fig. la. 



29. Base of leaf of N. major with the sheath opened. Intravaginal scales 



at the base of the sheath, one on each side ; enlarged ^. ' Compend. 

 Fl. It.,' I. c. fig. 1 m. 



30. Intravaginal scale of N. major; enlarged f. 'Compend. Fl. It.,' I. c, 



fig. lo. 



Plate 252. 



31. Transverse section of the middle of the leaf of N. graminea, Del. ; 



enlarged 1 ^". Magnus, 'Beitrage,' pi. vi., fig. 3. 



32. Transverse section of the side of the leaf of N. graminea, Del., from 



Celebes; enlarged 3 ^ s . Magnus, 'Beitrage,' pi. vi., fig. 2. 



