2. PoTAMOGETON.] I'JO. NAIADACE.E. 



Common in tanks in C'hota Nag-pur ! Shahalmd. J. DM. ! Probaljly to be found 

 in all districts of the province Ijut not collected. Jl. Aug.-Jan., perhaps all the 

 year round. Fr. found in April and May, and usually' fruits soon after flo^yering■. 

 The plant closelj' resembles the common English P. 'natans. 



Leaves mostlj' broadly elliptic and obscurelj' 13-15-nerved from the base; some 

 Behar specimens have, however, lanceolate-elliptic leaves about .3'3" by r3". 



2. P. javanicus, Hassl: 



Different looking, more slender than the last and with much smaller 

 leaves, ell. -oblong, ovate-oblong or elliptic, acute both ends, or sub- 

 obtuse, 5-7-nerved including the midrib, -0-15" long and petiole 

 shorter ; stipules -5-1" ; submerged leaves linear acuminate or 

 filiform. Spike -S-'S" long Avith flowers smaller than in P. indicuti 

 and the whorls more distant, peduncle as long or longer than the spike, 

 very slender. Sepals orbicular-cbovate. Drupels semi-globose 'OS" 

 long with stout hooked beak and ribs often toothed or tubercled. 



Shahabad, J.B.H. ! to Sikkim Tai'ai ! Chilka Lake, Lan-sov ! Probably also in 

 other parts of the province. Fl., Fr. Dec. -March. 



3. P. crispus, L. 



Stems slender, compressed, dichotomously branched with distichous 

 half-amplexicaul close-set oblong to linear acute or obtuse leaves 

 1-3" or up to 5" long, •1--3" broad Avith crisped and serrulate margins, 

 3-nerved. Petiole 0, stipules small obtuse caducous. Spike very 

 small •2--3" long, only 6-8-fld. Peduncles over V and exceeding the 

 upper leaves. Flowers very small, sepals -S--!" with the claw. 

 Drupels obliquely ovoid, •1--12" (-2" in English specimens), com- 

 pressed acuminate with straight beak. 

 Behar, J.D.II. ! Not uncommon in Chota Nagpur ! Fl. Dec-April. 



P. perfoliatus, L., occurs in the United Provinces not far west of our area and 

 will probably be found within it. The leaves are amplexicaul, o^-ate, cordate, 

 •7-3", upper opposite, 5-9-nerved. Spike dense-fld. 



4. P. mucronatus, Presh 



Leaves all submerged, petioled, elhptic- or oblong-lanceolate or 

 linear-oblong 3-7" by -S--?", acute or cuspidate, with a long point, 

 5-9- or more-nerved with acute or obtuse base. Petiole one-half or 

 one-third as long as the blade. Stipules 1-1-5", exceeding the petiole. 

 Spike 1-2" of interrupted groups or Avhorls of floAvers, very long- 

 peduncled. Sepals suborbicular, very shortly clawed. Drupels half- 

 orbicular, shortly beaked. 



Chaibassa tank, Singbhum, Wood {Bee. Snrv. Tnd.). 



5. P. pectinatus, L. 



Stem filiform, copiously distichously branched with filiform very 

 flaccid submerged alternate leaves 1-G" by -1" or much less, opaque 

 with slightly thickened or inrolled margins, 1-o-nerved, sometimes 

 •2" broad and 5-nerved (F.B.I.). Sheaths up to 7-nerved. Stipules 

 adnate to the leaf sheath with free points only. Flowers interruptedly 

 whorled on a spike -2-1" with long filiform peduncle. Drupels 

 dimidiate-obovoid, slightly convex ventrally, with strong lateral 

 ridges and when dry sometimes obscurely keeled dorsally, hardly 

 beaked. 



848 



