102 



ALISMACEAE 



3. Sagittaria greggii J. G. Smith. 



Gregg's Arrow-head. 



Fig. 214. 



Sagittaria greggii J. G. Smith, Rep. Mo. Bot. Gard. 6; 

 43. 1894. 



Plants partially emersed. 20-40 cm. tall. 

 Leaves about 1-2 dm. long, the terminal lobe 

 ovate to lanceolate, acute or slightly acumi- 

 nate, the basal lobes lanceolate or linear-lan- 

 ceolate, acuminate, about as long as the ter- 

 minal or longer, submerged leaves bladeless 

 or with an entire linear-lanceolate blade 3-5 

 cm. long; whorls of the inflorescence several 

 to many ; bracts lanceolate or linear-lanceolate, 

 acuminate, 15-30 mm. long; sepals oval to 

 obovate, becoming 6-8 mm. long ; corolla 

 mostly 1-2 cm. laroad, or more ; filaments 

 dilated at base; fruiting heads 8-15 mm. in 

 diameter ; achenes obovate to orbicular-obo- 

 vate, 2-3 mm. long ; thick-margined, the sides 

 with a thin-margined depression, the beak 

 minute, horizontal. 



Sloughs and slow running waterways. Austral 

 Zones; lower San Joaquin Valley, California, also in 

 Mexico. Type locality: Zamora, Michoacan, Mexico. 



4. Sagittaria sanfordii Greene. 

 Sanford's Arrow-head. Fig. 215. 



Sagittaria sanfordii Greene, Pittonia 2: 158. 1890. 



Plants emersed or partially submerged, erect 

 or ascending. Leaves sometimes represented by 

 3-sided phyllodia, the petioles spongy, very stout, 

 2-4 cm. thick at the base, the blades entire, 

 linear-lanceolate to oblong-lanceolate, mostly 10- 

 15 cm. long, acute, narrowed at the base ; scapes 

 shorter than the leaves, simple; pedicels 1.5-2 

 cm. long, becoming stout and recurved in fruit ; 

 bracts broad, 5-7 mm. long, united at the base ; 

 sepals ovate, 4-6 mm. long ; corolla about 2 cm. 

 broad; anthers oblong; fruiting head 12-14 mm. 

 in diameter ; achenes broadly cuneate, about 2 

 mm. long, winged on both margins, the beak short, 

 lateral, ascending, broadly triangular. 



In sloughs and slow running waterways, Upper Sonoran 

 Zone; Lower San Joaquin Valley, often growing in large 

 colonies. Type locality: sloughs of the Lower San Joa- 

 quin River about Stockton, California. 



5. Sagittaria montevidensis Cham. & 

 Sch. Montevideo Arrow-head. Fig. 216. 



Sagittaria montevidensis Cham. & Sch. Linnaea 2: 156. 

 1827. 



Plants emersed or partialh- submerged, 

 5-17 dm. tall. Leaf-blades hastate or sagittate, 

 1-6 dm. long, the basal lobes acute or acumi- 

 nate, more or less divergent, about as long as 

 the terminal ; scapes stout, sometimes 6-8 cm. 

 thick at the base; sepals becoming 10-15 mm. 

 long, obtuse, erect in fruit; corolla 2-4 cm. 

 broad, the petals white with a brownish purple 

 spot at the base ; filaments glandular-pubes- 

 cent ; fruiting heads 1.5-3 cm. in diameter; 

 achenes cuneate to rhombic-obovate. 2-i mm. 

 long, winged, the beak slender, horizontal or 

 obliciue, the faces unappendaged. 



In sloughs and slow running water courses in the 

 Lower San Joaquin Valley, also in the souttiern At- 

 lantic .States. Naturalized from .South America. Type 

 locality: Montevideo, Uruguay. 



