P. Graebner. — Potamogetonaceae. 



Schweden: Prov. Medelpad in stehendem Wasser! 

 Nota. Forma valde distincta, foliis plus quam 2 dm elongatis. 



Subvar. 3. brevifolius Tisel. Potam. suec. exsicc. (1896) n. 136. — Folia 

 omnibus partibus minora, ad 6 cm longa. 



Europa: Schweden: Prov. Södermanland. — Schweiz: Robenhausen (Jäggü). 



— Tirol (Zimmeter!). 



Var. ö. virescens Aschers, et Graebner, Synops. mitteleurop. Fl. I. (1897) 312. 



— P. rufeseens f. virescens Caspary in Schrift, physik.-ökonom. Ges. Königsberg XXIV. 

 III. (1883) 70. — P. alpinus forma viridis Tiselius Pot. suec. exsicc. n. 14. — Folia 

 (etiam siccata) viridia. 



Selten. — Bisher nur in Deutschland: Westpreußen, Ferse bei Pelplin!; Ost- 

 preußen: Kr. Oletzko (F. Schultz); Hessen: Weilburg (Rudio); Bayern: Oberpfalz, Hintere 

 Schwarzach westlich von Nürnberg (Schwarz!) 



Nota. Probabiliter prolem esse aestimo. 



Proles II. Casparyi (Kohts) Aschers, et Graebner, Synops. mitteleurop. Fl. I. (1897) 

 312, conf. Aschers, ex Weyl in Österr. bot. Zeitschr. XX. ( 1 870) 321. — P. Casparyi 

 Kohts in Österr. bot. Zeitschr. XX. (1870) 289. — P. Casparii Weyl Ö. B. Z. XX. 

 (1870) 321. — Caules simplices vel vix ramosi. Folia viridia, submersa remota, 

 basalia fere opposita, superiora alterna, sessilia, late lanceolata, internodiis brevioribus, 

 natantia approximata fere verticillata, spathulata, obtusa, sessilia vel in petiolum brevem 

 alatum attenuata. Spica laxa. 



Bisher nur in Deutschland: Westpreußen: Galgensee bei Berent (Kohts!). 



Nota. Planta habitu et characteribus valde distincta. 



Proles III. microstachys (Wolfg.) Graebner. — P. microstachys Wolfg. in Roem. 

 u. Schult. Mantissa III. (1827) 360. sens. strict. — P. rufeseens »forma angustifolia« 

 Cham, et Schlechtd. in Linnaea II. (1827) 211. — P. obrutus Woods, Class book (1845) 

 178, (1861) 675, conf. A. Bennett in Journ. of Bot. XLI1. (1904) 72. — Folia sub- 

 mersa angustiora, fluitantia saepissime absunt. Planta exsiccata nigrescens. 



Ostasien verbreitet (A. Bennett 1. c). 



Subspec. subflavus (Loret et Barrand.) Graebner. — P.subflavus Loret et Barrand. 

 Fl. Montp. (1876) 671, ed. 2. (1886) 502. — Caulis subramosus. Folia omnia 

 submersa, lanceolata vel lanceolato-elliptica utrinque attenuata, margine sinuato-crispula, 

 petiolata, petiolis foliorum latitudine subaequilongis, membranacea, pellucida, etiam sicca 

 subflava. Spica gracilis. Fructus parvi, lenticulari-compressi dorso subtricarinati. 



Frankreich: Montpellier, stehendes Wasser bei Mauguio (Duval-Jouve). — Blüht 

 Mai, Juni. 



37. P. Griffithii A. Bennett in Journ. of Bot. XXI. (1883) 65 t. 235; Bot. exch. 

 Club Brit. Isles 1884, 114; Journ. of Bot. XXIII. (1885) 376; Fryer in Journ. of Bot. 

 XXVI. (1888) 58. — P. alpinus X praelongus Aschers, et Graebn. Syn. I. (1897) 317. — 

 Folia submersa 1 — 3,2 dm longa et 1 — 3 cm lata (rarius latiora), late linearia vel 

 lanceolata vel subspathulata , subobtusa, natantia breviter (usque ad 4 cm) peduneulata, 

 spathulati-lanceolata, sensim in petiolum attenuata, obtusa, vix coriacea, saepe rufescentia. 

 Pollen et fructus non evoluti. 



Europa: England! 



Nota. Parte inferiore caulis saepe stipulae affixae sunt, quae laminis plus minus distinetis 

 instruetae sunt (conf. A. Fryer in Journ. of Bot. XXVI. [1888] 57). — Sempervirens (A. Bennett 

 in Bot. exch. Club Brit. Isles. Rep. f. 4884, 414; Babington in Journ. of Bot. XXIII. (4 885) 376 . — 

 Ex cl. Fryer (Monogr. Potam. Brit. Isles II. [4898] 34) non hybrida est, sed fructus ignoti 

 sunt. — Planta originis dubiosae. 



38. P. linguatus Hagström in Düsen Kenntn. Gefäßpfl. südl. Patagonien in 

 Oversigt K. Vet. Akad. Forhandl. IV. (1901) 259 — 62; A. Bennett in Journ. of Bot. XL. 

 (1902) 146. — Caulis 3 — 5 dm altus, rigidus, teres vel subteres, 3 — 4 mm crassus, 

 simplex vel vix ramosus, internodiis fere aequilongis, 4 — 5 cm longis. Folia submersa 

 tenuia, integerrima lanceolato-linguata, 9 — 10 cm longa, 2 ; 5 — 3,5 cm lata, obtusa, 



