Aponogeton.} CLXX. NAIADACE^;. (J. D. Hooker.) 565 



saying, " There is a var. if not a distinct species with hedgehog 2-seeded capsules, 

 but in all other respects the same." It follows that he, by inadvertence, describes 

 the follicles of A. echinatum as 6-seeded. 



4. A. microphyllum, Roxb. Fl. Ind. ii. 211; leaves very small 

 oblong long-petioled sides incurved, spike solitary, sepals much larger 

 than the 3 smooth 1-2-seeded follicles, seeds globose. Spathium microphyl- 

 lum, Voigt Sort. Suburb. Calcutt. 694. 



BHOTAN MTS. ; in damp places, RoxburgJi. 



I have seen no specimens, aud Roxburgh's description differs much from a 

 drawing in his collection. The latter represents a plant seven inches high, with a 

 smooth naked tuber, four leaves with sheathing petioles 1^ in. long, blade f by in. 

 concave recurved, apparently oblong acute, and quite opaque ; spike 1 in., clothed 

 with spreading white sepals^ in. long, and red-brown anthers. Roxburgh, on the 

 other hand, describes the leaves as many times shorter than the spike, spreading 

 close to the surface of the earth, 1 in. long by broad, and the spike as everywhere 

 covered with beautiful blue flowers. The globose seeds are remarkable. 



3. POTAITCOQETON, Linn. 



Submerged water-plants with creeping rootstock. Leaves submerged 

 or floating, opposite or alternate, entire or toothed ; stipules intrafoliaceous. 

 Flowers small, spicate on a scape rising from a membranous spathe, 

 ebracteate. Perianth- segments 4, concave, green, valvate. Anthers 4, 

 sessile on the segments, didymous, slits extrorse. Carpels 4, sessile, 

 1-celled, 1-ovuled ; stigma subsessile or decurrent, persistent ; ovule in- 

 serted in the inner angle of the cell, campylotropous. Drupelets small, 

 coriaceous or spongy. Seed subreniform ; embryo macropodal. Species 

 about 50, cosmopolitan. 



In determining the Indian species of Potamogeton I have had the invaluable 

 aid of Mr. Arthur Bennett, F.L.S., whose knowledge of the genus is as full as it is 

 accurate. 



* Upper or all the leaves floating. 



1. P. indicus, Roxb. Fl. Ind. i. 452 ; upper leaves floating oblong 

 elliptic or elliptic-lanceolate coriaceous, lower submerged longer narrower 

 membranous, stipules 1-1 i in. free, spike dense-fld., drupelets small 

 smooth. Kunth Enum. iii. 139 ; Don Prodr. 21 ; Wall. Cat. 5175 excl. F. ; 

 Grah. Cat. Bomb. PI 200; Dalz. & Gibs. Bomb. Fl. 248. P. Roxburghianus, 

 Schult.f. Hani. iii. 367. P. natans, Thw. Enum. 333. 



Throughout the plains of INDIA, ascending the Himalaya to 9000 ft. in Sikkim. 

 BURMA, Collett. CEYLON, Thwaites. DISTEIB. Malay and Sandwich Islds. 



Stem terete. Floating leaves 3-4 by 1-2^ in., alternate or uppermost opposite, 

 base acute or rounded, opaque; stipules as long as the petioles or shorter. Peduncle 

 stout or slender. Differs from P. natans especially in the shorter stipules and 

 smaller drupelets. 



2. P. natans, Linn. Sp. PI. 126 ; upper leaves floating oblong 

 elliptic or elliptic-lanceolate biplicate at the insertion of the petiole, sub- 

 merged few or 0, stipules 4-5 in. free spikes dense-fld., peduncle stout, 

 drupelets dorsally keeled shortly beaked. Kunth Enum. iii. 127. Reichb. 

 Ic. Fl. Germ.viL t. 50; Boiss. Fl. Orient, v. 15 ; Aitch. Cat. Panjab PI. 

 145. P. rufescens, Aitcli. I.e. 145. 



