202 METASPERMAE OF THE MINNESOTA VALLEY. 



Baillon, Hist. PI. IX, 22; Benth. and Hook., Gen. Pi. III. 123; Durand, 

 Incl. Gen. Phan. 345; Engler and Prantl, Nat. Pflanz. 3, I, 272 (Solereder): 

 Schenck, Palaeophyt. 704-709. 



Living species : 180 ± ; tropical and temperate regions. 

 Europe, 13: Russia, 2; S. Sts., 4; E. Sts., 3; Calif., 1. The 

 section which is represented in Asia and N. America contains 

 14 sps. 



Fossil species: 15-20; Cretaceous and Tertiary, Ne- 

 braska (Heer); Greenland (Heer); Europe (SajJorta); AiHsto- 

 lochiaephyllum in Lower Cretaceous, Potomac group (Fon- 

 taine) 1 sp. 



Aristolochia sipho L'Her. Stirp. Nov. Ease. I, 13 (1784). 

 A. macrophylla Lam. Enc. Meth. 1, 252 (1783). 

 SiiJhisia glabra Raf. Med. Fl. I. 6-5 (1828). 

 S. sipho Klotzsch, Monatsber. 602 (1859). 

 Wats, and Coult., Gray's Man. 6 ed. 445: Chap., Fl. S. St. 372; Upham, 

 Fl. Minn. 116; Engl. Solered. Nat. Pflanz. Ill, 1, 272. 



North America: Penn. to Minn, and Kan. 

 Minn, valley: Reported from N. E. districi and S. E. 

 edge; rare or local; rich woods and moist river banks. 



XXXII. POLYGONACEAE. Buckwheat 

 Family. 



Endlicher, Gen. PI. 304 (1840); Benth. and Hook., Gen. PI. Ill, 89 

 {1880); Dammer in Engler and Prantl, Nat. Pflanz. 3, I a, 1 (1891). 



Genera: 30; cosmopolitan; arborescent forms princi- 

 pally in tropical America; herbaceous in temperate regions; 

 shrubby in E. Mediterranean and Inland-sea region of Asia, 

 {Bentfiam and Hooker). Center of distr. N. temperate zone 

 (Dainmer). 



Species: 650-700 living; 12-15 fossil. 



RUMEX Linn. Gen. 300 (1737). 



Liapatliuin Moench, Meth. 355 (1794). 

 Acetosa Nkck. Elcm. II, 214 (1790). 

 Benth. and Hook., Gen. PI. Ill, 100; Durand, Ind. Gen. Phan. 342; 

 Engler and Prantl, Nat. Pflanz. 3, I a, 17 (Dammer). 



Living species: 150 described; 100± reduced; cosmo- 

 politan, but largely predominant in N. hemisphere. Europe, 

 36; Russia, 32; Russian Europe, 20; S. Sts., 9; Rocky mts., 5; 

 California, 12-13; Canada, 8; E. Sts., 7; PL King, 8?; PI. 

 Wheel., 3; N. America, 17-20. 



Runiex verticillatiis Linn. Spec. 334 (1753). 

 Wats, and Coult., Gray's Man. 6 ed. 438; Upham, Fl. Minn. 120; Mac, 

 Fl. Can. I, 416; Chap., Fl. S. St. 385; Cov., Fl. Ark. 216; Trelease, Rev. 

 Rum. 85. 



