196 



MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



[Vol. 9, No. 2 



long, the obolong anthers 0.4-1.3 mm long. Mature pistillate heads 0.7-2.5 cm in 

 diameter; achenes narrowly winged, 1.5-3 x 0.6- 1.5 mm, the faces with a single 

 short resin duct, or unadorned, the laterally or obliquely inserted beak 0.3-0.9 mm 

 long. 



1. Pistillate flowers without functional stamens; petals white with a purple 

 spot at the base; South American. 

 2. Pedicels of pistillate flowers somewhat thickened; basal lobes of 

 sagittate leaves somewhat divergent; warm temperate and tropical. 



4a, subsp. m ante vide ns is . 



2. Pedicels of pistillate flowers greatly inflated toward base of receptacle; 



basal lobes of sagittate leaves widely divergent; temperate. 4b. subsp. chilensis. 

 1. Pistillate flowers with a ring of functional stamens; petals all wbite; 

 North American. 



3. Leaves typically sagittate, if bladeless the phyllodia linear; inland 



plant. 4c. subsp. calycina. 



3. Leaves rarely sagittate, the phyllodia lanceolate or spatulate; tidal. 



4d. subsp. spongiosa . 



4a. Sagittaria montevidensis subsp. montevidensis. 



Sagittaria pugioniformis var. montevidensis Kuntze, Rev. Gen. 3: 328. 1898. 

 Sagittaria multinerva Larranaga, Escrit. Larr. 1: 1. 1922. 



Perennial. Leaves typically emersed, sagittate with linear to ovate blades and 

 somewhat divergent basal lobes, rarely submerged or floating, then the basal 

 lobes absent. Scapes with 3-12 whorls of flowers, simple or branching at the 

 lowest whorl. Bracts connate, the free ends elongate attenuate, to 2.5 cm long. 

 Pistillate flowers rarely with a ring of functional stamens; sepals covering more 

 than one-half of the receptacle at maturity; petals with a purple spot at base. 

 Stamens numerous, the linear sparsely pubescent filaments 1.8-3.5 mm long. 

 Mature pistillate heads 1.5-2.5 cm in diameter; achenes 2-3 x 1-1.5 mm, the resin 

 duct present or obsolete (FIG. 2 e, f.) 



Type collection: Sellout s.w., Rio Grande do Sul, Brazil (holotype, not seen, 

 Berlin; photograph of holotype GH, US). At the time this species was described 

 Uruguay was a part of the Brazilian province of Montevideo whose borders in- 

 cluded Rio Grande do Sul, hence the specific epithet. 



Distribution: Warm-temperate South America, east of the Andes; sporadically 

 northward in the tropics to coastal Ecuador; introduced or adventive elsewhere. 

 Collections examined from Argentina, Bolivia, Brazil, Ecuador, Paraguay, Peru 

 and Uruguay. Adventive but apparently not persisting along the coast of the south- 

 eastern United States. Cultivated in many botanical gardens throughout the world 

 including Africa, Java, and the United States. (FIG« 2.) 



4b» Sagittaria montevidensis subsp. chilensis (Cham. & Schecht.) Bogin, comb, 

 nov. 



Sagittaria chilensis Cham. & Schlecht. Linnaea 2: 155. 1827. 

 Sagittaria heterophylla Bert, ex Steud. Nom. ed. 2. 2: 491. 1840. Nomen nudum. 

 Sagittaria incrassata S^eud. Nom. ed. 2. 2: 491. 1840. Nomen nudum. 

 Sagittaria andina Phil. Linnaea 29: 45. 1857. 



Sagittaria montevidensis var. scabra Micheli in DC. Monogr. Phan. 3: 76. 1881. 

 Sagittaria alismae folia Phil, ex Micheli in DC. Monogr. Phan. 3: 76. 1881. Nomen 

 nudum. 



Sagittaria taeniaefolia Phil, ex Micheli in DC. Monogr. Phan. 3: 76. 1881. Nomen nudum. 

 Sagittaria pugioniformis var. acutifolia Kuntze, Rev. Gen. 3(2): 328. 1898. 

 Sagittaria pugioniformis var. andina (Phil.) Kuntze, Pev. Gen. 3(2): 328. 1898. 

 Sagittaria pugioniformis var. chilensis (Cham. & Schlecht.) Kuntze, Rev. Gen. 3(2): 

 328. 1898. 



