755 



99. A 1:358 d. Cov 200. 



Type locality: "on Deer creek at Las- 

 sens' in the upper Sacramento Valley." 

 Variety WISLIZEKTI Wat. Br 1:204 Cruz. 

 A 1:359 d. 



P. MCNrLIPiraA Ait. Hort Kew 3:408. 

 Cov 200. SBer mts, etc. Canada. B 2:92 

 as 



P. MOKTICOLA Mert ex Loud Arb 3: 

 1645. Z 1:274. tremula fide IK. 

 P. TREMTTXnOISES Michx Fl 2:243. B 

 2:91. 



P. TRISHOCARFA T & G, Hook Ic 9: 

 878. Cov 200. Ab 99. Da 16, B 2:91. Br 

 1:216 Rosa. Greene, Cal ac b 2:412 

 Cruz. A 1:359 d. 



Genus POROPHYLL.UM Vtiillant. 

 Bth. 'bot Sulph 29. B 1 :3?'.;. P. 1:205. 

 POROPHYLLUM GRACILE Benth. 



Texas; SD; Cedro^; CD! Magdaiena Is- 

 land (Br). 



P. GREGGH G, PI Wright lr!20. = 

 gracile et scoparium fide IK. 

 Variety MINOR G. B 1:399 as gracile. 

 PORTEREi&IiA T, Hayd R Geol Surv 

 Mcnt 488 (1872). La'urentia fide IK. 

 P. CARNUIiOSA T, Ic. Parry, Wyo 17. 

 (Lobelia carnosula Bth.) B 1:144 as 

 Lauren tia carnosula. 

 POTESIUM L. 



P. AlOTTTUM Nutt, Hook Fl 1:18. B 1: 

 186. 



P. OPPICIETALE B&H. B 1:186. 

 PORTUIiAGACEA A 1:163 d. 

 PORTUXiACA L, syst ed 1 (1735). A 1: 

 163 d. 



P. GRA23j2IFZiORA Hook, bot mag t 

 2885. B 1 



P. OIiERACEA L, sp pi 445. B 1:74. 

 Da 3. Ab H2. A 1:1 fi4 D. 

 P. FIZiOSA . L; sp pi 44-5. B 1:74. 

 P. RETTJ3A E, PI Lindh 2:154. Br, Colo 

 233. B ]:74. 

 Genus POTAMOGETON Tournefort. 



Per herbs: Ivs alt or uppermost oft 

 opp, oft of 2 kinds, submerged and 

 floating ,the floating elliptic or ovate, 

 the submerged linear: spikes sheathed 

 by stipules in bud: ped axy, bearing 

 sm perfect fls; perianth seg 4, herbace- 

 ous concave, valvate in the bud. short- 

 clawed: sta 4, inserted on claw.s of per- 

 ianth seg; anth sessile: ova 4, sessile 

 distinct 1-celled, 1-ovuled, attenuate in- 

 to a sh erect or recurved sty. 

 P. AMPLIFQX.ITJS Tuckerm, Am J sc 

 sr 1, 45:38. B 2:196. 



P. CLAYTONI Tuckerm, Ic. B 2:195. Ha 

 54. 



P. COMFRESSUS Fries. B 2:197 as 

 zosteraefolius. 



P. GRAMTSTEUS L; sp pi 127. B 2:196. 

 P. HETEROPHYI 1=113 Schreb. spicil 

 Fl Lips 21. B 2:196 as gramineus. 

 P. FOUOSTTS Rafin, Med rep NY. sr 3, 

 2:409 r^ll). p;v .cle !"'. 



Variety CAZalFOSNICTTJ Moron -. 



Sts .3-1 m Ig, much branched, flat- 

 tened or winged; Ivs 3-5 cm Ig, 2 mm 

 wide, 3-nerved or sometimes 5-nerved 

 toward base; stipules free from the 

 Ivs, sm w. becoming setose; peduncles 

 8-12 mm Ig, erect, clavate, flattened; 

 spikes subcapitate, 6-12 fld; fr lenticu- 

 lar or nearly orbicular, about 2 ir>m Ig, 

 3-keeled on 'back, middle keel winged. 

 POTAMOGETON PUSILLUS Linn. 



sinuate-dentate, face strongly angled 

 or arched; sty apical. Lvs submerged. 

 Ab 11. "Occasional in streams and ir- 

 rigating ditches in our interior valleys. 

 Je-S." 



P. FLUITANS Pursh Fl 1:120. 

 Claytoni fide IK. (Roth, Tent Fl Germ 

 1:72; 2:202 ^lonchites fide Ab 10?). 



ITES Tuckerin, Am J oc sr 

 2, 6:22G. lucens fide IK. Ab 10. B 2: 

 196. 



Sts 1-2 m Ig. much branched; float- 

 ing Ivs rather thin, elliptic, pointed' at 

 both ends, 5-10 cm Ig; submerged Ivs 

 linear-lanceolate, 10-15 cm Ig, 4-20 mm 

 wide, rounded at base or tapering into 

 a petiole; stipules 2-8 cm Ig, free fr in 

 Ivs; peduncles thickening upward. 4-6 

 cm Ig; spikes dense. 2-1. cm Ig; fr 4 mm 

 ;g. '.M;> hj-je :iies smooth, 3- 



on 



POTAMOGETON LUCENS Linn. 



"xj, sp pi 126. B 2:196. Parish Er 6:85, 



i^enasquitas creek. Sl> Co. 



F. MABXHITS L, sp ' pi l-'V. Eu. B 



P. MONVANUM Presl, p.el Haenk 'i: 85. 



d 2:196 as lonchites? 



POTAMOGETON NATANS Linn. 



L,. sp pi 126. B 2:195, 196 s. Ab 10, 



Bear. 



Sts 1-1.5 m Ig, simple or sparingly 



branched; floating Ivs thick ovate-ellip- 



lanceolate, rounded or subcordate 



at bas^J 4-8 cm Ig, mostly sh'er than 



. ; submerged Ivs reduced to phyl- 



lodes or bladeless petioles; peduncle as 



thick' as st, 4-8 cm Ig; spike dei, 



cm Ig; fr turgid. 4 mm Ig, nar'ly obo- 



void; nutlet pitted on the sides, 2- 



grooved on back. 



1-*. KI A O ARE 39 SIS Tuckerm, Am J sc 

 sr 2, 7:354. B 2:197. 



P. PAUCIFI.ORUS Pursh, Fl 1:21. B 

 2:197. (Parish, 940 = var.) 

 P. TRI'CiHOIDES C & S, Linnaea 2:17. r >. 

 Eu. (Bth 341 == pusillus fide B 2:198.) 

 P. ZOSTERACETTS Fries, Nov Fl Suec 

 ed 2. 51. B 2:198. 



P. ZOSTSRAEPCljIUS Schum, En PI 

 Saell 1:50. B 2:197. 



P. OBTTTSIFOIiITTS M & K, Deutch Fl 

 1-855. (Parish 940 = pauciflorus var. 

 B 2:198. Da 17. Ab 11. 

 POTAMOGETON PECTINATUS Linn. 



Sts .3-1 m Ig, slender, much branched, 

 branches repeatedly forking: Ivs seta- 

 ceous, attenuate to apex, 1-nerved, oft 

 capillary or nerveless, 2-10 cm Ig; stip- 

 ules half free, 1-2 cm Ig, their sheaths 

 scarious on margins; peduncles fili- 

 form, 4-10 cm Ig; spike 1-4 cm Ig; fls 

 in whorls; fr obliquely obovoid, about 

 4 mm Ig, with 2 obscure lateral ridges 

 on back"; sty straight or curved, facial: 

 Ivs submerged. 

 P. PERPOLIATUS L, sp pi 126. B 2: 



197. Parry, Wyo 18. 



P. PRAEX.ONTGUS Wulf, Roem Arch 3 



(3):331. B 2:197. Eu. 



P. PROTEUS C & S, Linnaea 2:196. 



Variety 1UCESFS C & S, Linnaea 2:197. 



B 2:197 as sp. 



L, sp pi 127. B 2:198. 



P. ROBBLtcSH Oakes, Hovey Mag 7: 



180. B 2:198. 



P. RUFESCEII"-? Schrad, in cham Adn 



ad Fl Berol 1815:4. B 2:195. 



