OF NAIAS GRj\»*INEA, VAR. DELILEI. 75 



Fig. 55. JV. graminea. Le?**'^^^^*^ from leaf of second pair ; enlarged \*. 



56 & 57. N.flexili'i- — Leaf-sheath from Scotch specimens ; enlarged -y. 



58. N. qramw''-''^- — Spines on margin of auricles ; enlarged -\^. 



59. N,jiii-orvlis. — Spines on margin of auricles from Loch Oluny; they 



are the first four which occur on the left shoulder of fig. 57, above 

 the minute spine, nearest the base of the sheath ; enlarged -\^. 



60-65. iV. graminea. — Transverse sections of leaves, beginning near the 

 summit ; enlarged -\^-. 



66. JV. alaganensis. — Libriform cells in margin of leaf, from Malin- 

 verni's Italian specimens ; enlarged if-S-. The libriform cells are 

 the long cells without cell-contents. 



6j. N. graminea. — Young antheriferous and pistilliferous flowers grow- 

 ing side by side ; enlarged y®-. 



68. -ZV. graminea. — Older antheriferous and pistilliferous flowers grow- 



ing side by side ; enlarged -j® . 



69. N. graminea. — Portion of central inflorescence ; enlarged -V . 



70. N. graminea. — Pistilliferous flower with contiguous bracts ; enlarged 



1 8 

 "T- 



71. N. graminea. — Young pistilKferous flower ; enlarged V-. 



72 & 73. N. graminea. — Young pistilhferous flowers, showing the stig- 



matoid appendages ; enlarged -V-. 

 74 & 75. N. graminea. — Young antheriferous flowers; enlarged \^-. 

 76. N. graminea. — Young antheriferous flower, showing immature 



pollen ; enlarged -\^-. 

 jj. N. graminea. — Antheriferous flower not fully ripe ; enlarged -\^. 



78. N. graminea. — Mature antheriferous flower ; enlarged -V~. 



79. N. graminea. — G-lobose pollen ; enlarged ^\^. 



80. N. graminea. — Elliptico-cylindrical pollen ; enlarged J-f ^. 



81. N. graminea. — Fruit, with immature pistilliferous flower in the 



same bract ; enlarged V . 

 82 & 83. N. graminea. — Fruits nearly mature; enlarged -'/-. 



84. N. graminea. — Supposed ridges and pits, of hexagonal outline, on 



surface of fruit, as seen with a y^ objective, Lieberkuhn, and Kelner 

 B eyepiece. 



85. N.flexilis. — Kidges and pits, of quadrangular outline, on surface of 



fruit, as seen with a ^Ij objective, Lieberkuhn, and a Eelner B eye- 

 piece. 



86. N. graminea. — Three mature fruits and an immature pistilliferous 



flower in the same verticil ; enlarged V-. 



87. N. flexilis. — Mature fruit from Loch-Oluny specimen ; enlarged -',4, 



88. iV! graminea. — Perianth removed from fruit; enlarged -V. 



89. N. graminea. — Transverse section of the root ; enlarged V. 



