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685 



POTAMOGETONACEAE: POTAMOGETON. 



686 



ovuLA solitaria pro loculo, pendula ciirvata atropa, micro- 

 pyle infora. Xrx plus minus subdrupacea complanatu 

 dorso saepius cariuata apiciilata obliqua sessilis, endo- 

 carpio teuui sublignosccnte vel rarius duriore. Semen 

 inicinato-curvatum vol plus minus totius longitudinis 

 spiralitor tortum, eudopleura tenui membranacea; embryo 

 forma scminis basi incrassatus, albumine nullo. 



Herbae aquaticae perennes, saepe ope Mhernacu- 

 lorum e ramis orhmdorum rarius infernodiorum in iuhera 

 incrassaforicm perennmites. Folia conformia tunc omnia 

 siihmersa viilgo graminea rarius latlora lanceolata vel 

 nhlonga vel ellipfka sessilia, nunc mferiora sola liujiis 

 naturae, stiperiora contra duriora saep'uis coriacea pefio- 

 lata subparalleli- vel ciirvato-nervia, basi vaginata et supra 

 vaginam Ugula instructa vel stipuUs intravaglnalibus 

 amplexicaulibus mtmita: SQUAmulae intravaginales sub- 

 idatae vel lanceolatae vel latiiisctde triangulares 2 — od. 

 Flores in spicas 2 — cc- floras conflati, alterni vel 

 saepissime verticillati, verticillis alternantibus. 



Species in toto vix ultra 60, at plures in multas inepte 

 divisae; nonnuUae supra oi'bem late rtispersae nee regiones 

 arcticas eifiigientes. 



CLAVIS SPECIERUM BRASILIENSIUM. 



I. Folia Imsi non in vajjiuam dilafata, at stipula amplexicaiili iniinita. 

 A. Folia heteroniorpha , siibniersa teniiioni angnstioiii, 

 nnfanlia duriora siih(*oruieea, vel omnia cnnsistentia 

 iilteriore Series I. HETEROPHYLLI Koch. 



a. Nuoes pro lala mnjusculae nhique inanes, folia ob- 

 longa acnminata l>nsi i)ariter acuta, spica crassa brevis 



1. P, FLL'ITANS Rth. 



b. Nuces dnplo et ultra breviores maturae semper embryouem iu- 

 cludentes. 



a. Nuces IVagillimae parvae (1mm. longae); spioa 

 elongata tenuis; folia natantia subauthesievanida, 

 at caulis stipnlis maximis iuvohitus 



2- P. STEN0STACHY8 K. Sch. 



p. Naees dnriores mediocres (3 mm. longae); spica 

 brevis; folia natantia sub antbesi obvia lineari- 

 lanceolata,stipuIae breves 3. P. sci.erocarpus K. Sch, 

 li. Folia bomomorpha. 



a. Folia oblonga vel oblougo-lauceolata 



Series U. IIOMOPHYLLI Koch, 



4. P- LUCENS Liuii. 



k Folia linearia, graminea . Series III CHLOEPHYLU Koch- 

 a. Stipulae alte lacerato-fissae; pistilla semper 2 



5. P. Ulei K, Sch. 

 p. Stipulae baud lacerato-fissae; pistilla 4. 



* Nuces dorso alato-carinatae; folia pro rata 

 late linearia .... 6, P. polyoon'US Cham, et Scbb 

 •• Nuces dorso vix carinatae; folia angustissima 



linearia 7. P. fusillus Liqn, 



U. Folia basi in vaginam apice ligula muuitam dilatata 



Serie.sIV. COLEOPHYLLI Koch. 



A. Folia plana vel biconvexa. 



a. Folia saltern superiora anguste linearia 



8- P. PECT1NATU8 Linn, 



h. Folia omuialatinscule linearia 9. P. striates R. et P. 



B, Folia supra coucava, subtus convexa, spongio,«o-carno- 

 Bula, nuces quam iliac prior um duplo breviores (more 



P. marhii LinnJ 10. P. aulacophtu^us K. Sch. 



Potamoget. 



1. POTAMOGETONFLUITANSRoTU: herba aquatica 

 parte intiina tantum solo atiixa, ceterum fluitaus, caulibus 

 tereiibus sice, quiilem striatis pro rata validiusculis; foliis 

 inferioribus submeisia alternis longe vel loiigispime rarias 

 breviter petiolatis oblongis lanceukto-oUuugis rarius lauceo- 

 latis aciitis raro acuminatis basi plus minus raanifeste in 

 petiolum attenuatis membrauaceis plurinerviis; foliis natantibus 

 durioribus coriaceis brevius petiolatis, saepe oblongis vel 

 ovato-oblongis apice breviter acuminatis basi breviuscule acu- 

 minatis vel nunc subrotundatis , nervo mediano crasso et 

 lateralibus pluribus praesertim subtus conspicuis perciirsis; 

 stipulis pro rata magnis amplexicaulibus ambitu obloiig<>- 

 triangularibus acutis hyalino-membranaceis, basi firmioribus, 

 nervis binis magis pi-ominentibns pluribus lateralibus et inter 

 priores positis percursis striatis; squamulis intravaginalibus 

 lanceolato - triangularibns attenuato - acuminatis acatissiniis; 

 spica pedunculata, densa vel subinterrupla, pedunculis ralidis 

 nunc apicom versns iiicrassalis, terotibns striatis vnlgo caule 

 crassioribus ; floribns sessilibus primum dense aggregatis dein 

 laxins dispositis; pi^rigonii phyllis ungiiiculatis subrliombeis 

 acutis basi attenuatis; staminibus minute apiculatis; cjirpiiliis 

 semiovatis, stigmatibns sessilibus oblique trunca!is, nuce com- 

 planata breviter rostrata dorso subalato - costata , lateribus 

 costis 2 prominentibus percursa. 



Potamofjetou Jhiiiatis Roth, Tent. fl. Germ. L 75, II. 

 202; Nolte, Nov. fl. Hols. IfJ ; Chant, et SchJrrlf. hi Linnaea 



II. 210; Irmlsch, Potameen Berl. 1858; Koch, Syn. ed. II. 776; 

 Rchh. Icon. VII. t. XLIX; Godr. et Gren. FL Fr. Ill 

 S12; Aschers. Fl. Mark Brandenh. 657 ; A. Gray Man. ed. 

 V. 516; Griseh. Fl Br. W.-Ind Isl. 506; Willk. ef Lmig. 

 Fl. Ilisp. I. 28; Boiss. Fl. orient. V. 16; Arih. Bennett in 

 Joiirn. of hot. XXII I .S76 ; Fryer in Jonrn. of hot, XXV. 

 307, XXVI. 273; Macoun Cat. pi Ganud. V. 3G9. 



Potamogeton immihis Wolfg. in Roetn. ef Schulf. Maid. 



III. ad Syst. 3d4. 



Potamogeton ohlongus Mey. Chlor. Uanover. 519, non Viv. 

 Potamogeton nalans L. var. angustatus Mert. el Koch, 

 Fl Beutschl I. S30 ; Kth. Enum. pi III 128. 



Potamogeton nodosus Poir. in Lam. Encycl XII. 535; 



Cham, in Linn. 11. 222. 



Potamogeton Canariensis Lk. f in L. v. Buch, Canar. 138. 



Potamogeton occidentalis Sieb.f Fl ets. Martin, ap. 

 Cham, in Linn. II. 224. 



? Potamogeton NuttallH Cham. I c 226. 



Potamogeton Wahiensis Cham.! I c. 



Potamogeton BiUiotti F. Scltz. PI exsicc. 



Potamogeton lonchiten Macoun. in Cat. plant. Canad. 



IV. 83, non Tuckerm. 



Herba nquatica demersa foliis quibii.s(l;im tintum uatantihn?, spicis 

 florentibus supra aquam poricclis, caui.ks 1,3—3 m. longi , infrnip sim- 

 plices vel sul)siiiiplice8 in regioue florali ramosi, ca. 2 mm. crassi vel pauIo 

 ultra vel iufra; ixtrrkodia inferiora infer pe remota, infinia hreviora 

 ca. 1—1,5 cm. looga, superiura regionis vegetativac 7-10 cm. longii, 

 in regione florali ti.m ahbreviata lit folia snbopposita evadant , elemeiiU 

 pariiim iniieqnaliter alte inserta. Petioi.us fomoRUM aqvaticorum mine 

 6—10 cm. lougns, uunc niiilto lonpioT nsqne ad 20 cm. metiens nunc oh 

 lauiiuam scnsim et valde eloiigato-attenuatum subnuHus; foliorl'm xa- 

 TANTitJM 4—7 cm. loDgus, validior et cra^sior supra statu vivo subcon- 



89 



