REVISION OF THE GENUS NAJAS. 431 



33. Portion of a leaf-blade from same specimen, x 20. 



3 lr-37. To show variation in form of Icaf-slieath. x 20. 34, 35 from opposite leaves ; 36 from a leaf 



a little higlicr on the same shoot (specimen in Herb. Link.) ; 37 from a (hlTcrcnt plant 



(Tranquebar, Klein) . 



38. Intravaginal scale, x 40, 



39. Young male flower, x 30. Specimen from Tranquobar. 



40. Mature „ x 15. „ „ 



41. Male flower showing enlarged pedicel, laterally split spathc, and rolling back of perianth-lobes. 



X 10. Specimen from Tranquebar. 



42. Pollen from same flower. Much enlarged. 



43. Female flower showing one stigma protruding from mouth of spathc. x 20. Specimen from 



Tranquebar. 

 44-. Same as fig. 43 after removal of spathe. x 30. 



45. Seed, x 15. Specimen from Tranquebar. 



Najas Wehoitschii. (Figs. 4G to 54.) 



46. Front view of leaf -sheath, x 20. 



47. Apex of leaf, x 15. 



48. Intravaginal scale, x 15. 



49. Marginal leaf-tooth. Much enlarged. 



50. Male flower. X 20. 



51. „ showing elongation of pedicel (pe) and rupture of spathe (*) . x 12. 



52. Female flower; the two stigmas [st) protrude from the mouth of the spathe (s). X 30. 



Plate XL. 



53. Seed, x 10. 



54. Markings on seed-coat. Much enlarged. 



Najas madagascariensis. (Figs. 55 to 63.) 



55. Side view of leaf -sheath with rounded shoulders, x 14. 



56. Leaf-sheath with auricled shoulders, x 10. 



57. Young male flower, x 30. 



58. Mature „ X 16. 



59. Female flower, x 22, 



60. The same after fertilization. X 12. 



61. Tip of same flower as in fig. 60 after removal of spathe, showing the two stigmas under somewhat 



higher magnification. 



62. Seed, x 5. 



63. Lower part of seed more highly magnified to show markings on seed-coat, X 35. 



Najas Schweiyipirthii. (Figs. 64 to G7.) 

 (54, Front view of leaf-sheath. x 40. 



65. Scarcely mature male flower, x 50. 



66. Male flower, showing anther-dehiscence. X 12. 



67. Female flower, x 30. 



Najas IVrif/hiiana. (Figs. 68 to 74.) 



68. Front view of leaf-sheath, x 10. Specimen from Pernambuco [Ridley). 



69. Male flower. X 30. Specimen from Cuba ( Wright) . 



70. Female flower, x 18. „ „ 



