276 



J. O. HAGSTKOM, CRITICAL RESEARCHES ON THE POTAMOGETONS. 



petiolatus Wolfg. — 184, 189, 241. 



Phialcs Post, PI. Postianse fasc. VI, in Bull. Herb. Boiss. 



I, 1893, 409. — 74. 

 pliialensis Post, 1. c. — 60. 

 philippinensis Ar. Benn. — 57. 

 pinguis Tis., Pot. suec. exs. Ill, 1897, n. 126: pect. L., 



1 — 49. 

 pinnatus Fischek, I. c, 1907, 116: pusillus L., f. 

 pinnatus Waltek, FI. Carol. 1788, 90 (= Myriophyll. 



scabraium, ex Schult., Mant.). 

 planifoUus Metek, Chloris han. 1836, 523: crispus L., 



V. — 60. 

 planiagineus Du Ckoz. — 155, 178. 

 Plantago Bastard. — 176. 

 platycarpus FisCH. — 102. 

 plaiyphyllus Meter, 1. c, 520: gramin. L., v. (is plathy- 



phylliis RcHB. = Zisi M. & K.). — 207. 

 pleiophyllus Hagstr. — 159. 

 polaris Hagstk. — 17, 19. 

 polygonifollns Potjer. — 5, 67, 146—150, 175—180, 



182, 185, 192, 193, 215, 220, 263. 

 polygonif. X gramin. (P. Seemenii AsCH. & Gr. ). — 231, 



232. 

 polygonif. X gramin. ? ex Eour: P. variifoliits Thore 



ex E. — 193. 

 polygonif. X heteroph. f ex Bbeby, ap. Frtek, Pot. Brit. 



Isles, 1898, 21: polygonif. Poure. f. cancellata Fryer, 



1. c. — 178. 

 polygonif. X prcelongus (P. Macvicarii Ar. Benn. in Ann. 



of Scott. Nat. Hist., 1907, 106) ex Graebn. Pot., 



in Englee, I. c., 1907, 139. 

 polygoniformis Hagstr. — 113. 

 polygonus Cham. & Scm. — 67, 80—82, 85, 108, 112 



—113. 

 polyphyllus MoR., in Cotjlt., Bot. Gaz. V, 1880, 51: jm- 



sillus L., V. — 124, 125. 

 polystachyus Schultes, Mantissa in vol. Ill C. aLiNNE 



Syst. etc., 1827, 364: pecf. L., v. 

 porcaius MuiiL., Cat. pi. Amer. sept., 1813, 18 ( »Furrow- 



leaved Pondweed » Muhl. — Specimens in herb. 



J. E. Sm., lab. »P. porefito?» n:o 64, 1793» is said to 



bo P. spirillus TuCK., ex Ar. Benn. in The Journ. 



Bot. 1890, 297). 

 porrectifolius Ar. Benn. ap. Geaebner, Pot. in Englee, 



]. c, 1907, 83: Zizii M. K., var. 

 porrigens Hagstr. — 169, 172. 

 poHoricensis Graebn. in Urban, Symb. autill. IV, 1903, 



73: pensylvanicus Ch. ct Schl., v. — 140, 155. 

 prwlongifolius Piscii., 1. c, 46: alpin. Balb., f. 

 prailoiigifolius Tis. — 224 — 227, 230. 

 priBlongus Wulfen. — 4, 7, 10, 12, 61, 62, 63, 144, 149, 



152, 177, 215, 228, 234, 241, 243—247, 250—255, 



257, 258. 

 prcel. X crispus ex Ascii. & Gr., Syn. mitt. Fl. I, 1897, 



338. 

 prwl. X gramin. ex Ascii. & Ge., 1. c, 330. 

 prcel. X heierophyllus ? ex Ae. Benn. in Journ of Bot. 



1903, 166. 

 prcel. X lucens ? (P. decipiens Nolte) ex AscH., Flora 



Prov. Brand, etc. 1864, 662. — 243. 



prcel. X polygonif. (P. Macvicarii Ae. Benn., in Ann. 



Scott. Nat. Hist. 1907, 106). 

 prcel. X Zizii ex Graebner, Pot. in Engler, 1. c, 1907, 



139. 

 Preussii Ar. Benn. — 87, 108, 114, 129. 

 prolixus Koch, Syn. Fl. Germ, et Helv. 1844, 775: na- 



tans L., V. — 192. 

 prolixus Hagstr. — 254, 256. 

 promoutoricus Hagstr. — 175, 182 — 183. 

 protensus Asch. & Gr., Syn. etc. 1897, 314: perfol. L., 



subv. 

 protensus Cham. & Schl., in Linnaea 1827, 190: perfol. 



L., f. 

 protensus FiscH., 1. c, 1907, 37: nutans L. f. 

 protensus FiscH., 1. c, 61: Schreberi P., f. 

 protensus Wallr. — 48. 



Proteus Cham. & Schl. — 205, 210, 221, 233. 

 prussicus Hagstr. (alpinus X perfoliatus). — 148. 

 pseudo-densus Asch. & Gr., Synopsis etc., 1897, 314: 



perfol. L., var. — 256. 

 pseudo-fluitans Stme, Engl. Bot. IX, 1869, 28: poly- 

 gonif. PouRR., var. — 178. 

 pseudohicens Hagstr. (illinoens. X luc.). — 199, 200. 

 pseudomarinus Ar. Benn. in Trans. Norf. & Norw. Nat. 



Hist. Soc, 1882, 381: pectin. L., v. 

 pseudo-nitens Ar. Benn. in Journ. of Bot. 1881, 344: he- 



terophyllus Schreb., v. — 207, 231. 

 psendopolygonus Hagstr. — 81. 



pseudo-rutilus Ar. Benn., in 1. c, 1901, 4: pus. L., v. 

 pseudo-Zizii Hagstr. (P. gram. X illin. X lucens). — 



200, 210. 

 psilostachyus Gdssone, Fl. sic. Synopsis II, 1845, 790: 



luc. L., var. 

 pulcliellus Tis. — 244, 245. 

 pnlcher Tuckerm. — 10, 151, 153, 158. 

 pulcherrimus Hagstr. — 214. 

 pumilus Nuttall, ap. Ar. Benn., Bem. etc. in Ann. 



Naturh. Hofm. Wieu. 1892, 292 (= Bobbinsii 



Oakes, ex Benn., 1. c). 

 pumilus WoLFG. — 139. 

 purpurascens Seidl, in Pkesl, Fl. Cecil. 1819, 37. — 141, 



142. 

 Purshii Tuck., Observ. in Am. Journ. Sci. and Arts, 



1848, 228. — 196. 

 pusilliformis Hagstr. (mucronaius X pus.). — 97 — 98. 

 pusilloides Hagstr. — 112, 115. 

 piisiHflS L. — 9, 13, 63, 64, 72, 75, 76, 88, 90, 91, 93, 94, 



97—104, 107, 115, 117, 118, 120—129, 134, 149, 



150, 195, 259, 262, 263. 

 pusillus X trich. (P. franconicus FisCH. ). — 104, 126. 

 pasillus X Vaseyi (P. lateralis MoR. ) ex Hagstr. — 



126, 127. 

 puyensis Hagstr., New Pot. in Bot. Not. 1908, 107: ar- 



gutulus Hagstr., f. 

 pycnostegus Kihlm. ap. Hagstr. Cfr. Tis., I. c. III, 



1897, notula; 115—116. — 16, 18. 

 pygmwoides Hagstr. — 192. 

 pygmwus Gaudin, Fl. helv. I, 1828, 467: nutans L., v. 



— 192. 

 pygmwus Hagstr. — 124. 



