127. Jl INC AGIN ACEAE 275 



1. Leaves ovate to cordate: stamens 12-21: aehenes 40 or more, 

 brown, beaked. 

 2. Scape erect, 10-30 cm tall: stamens 12; style longer than tlie 

 ovary; shores of ponds, rare. June-July [E. cordifolius 



sensu auth., non (L.) Griseb.] E. rostratus (Nutt.) Engelm. 



2. Scape prostrate, proliferous; stamens about 20; style shorter 

 than the ovary; swamps, rare. Junt'-July [E. radicans 

 (Nutt.) Engelm.] E. cordijolius (L.) Griseb. 



3. Sagittaria L. — Arrowhead 

 {Lophotocarpus T.Durand) 



1. Fruiting" pedicels thickened, spreading or recurved; sepals sub- 

 orbicular, surrounding the mature fruit; lower flowers perfect, 

 the upper .staminate with 9-15 stamens; leaves sagittate; shal- 

 low water, rare or local. [L. calycinus (Engelm.) J.G.Sm.] 



-- - S. calycinus Engelm. 



1 . Fruiting pedicels not thickened, ascending; sepals spreading or 

 reflexed in fruit; lower flowers pistillate, the upper staminate 

 with numerous stamens. 

 2. Leaves sagittate; stamens with glabrous filaments. 



3. Bracts of the inflorescence ovate, obtusish; beak of the 

 achcne horizontal; shallow water. July-Sept. C'ommon 



Arrowhead S. latijoUa \\ illd. 



3. Bracts lanceolate, acuminate; beak erect. 



4. Aehenes 2 mm long, with thick equal wings on both mar- 

 gins, the beak 0.5 mm long; shallow water. July-Sept. 



.S". cuncata Sheld. 



4. Aehenes 2.5-3 mm long, with thin, unequal wings; beak 

 1-1.5 mm long; muddy shores, or in ditches, common. 



July-Sept. .-.. S. hrevirostra Mack. & Bush 



2. Leaves linear, lanceolate, or oval (rarely .sagittate) ; filaments 

 more or less glandular-pubescent. 

 5. Aehenes 3 mm long, the beak 1.5 mm long; pedicels very 

 short, the pistillate flowers nearly sessile; ditches or 



muddy shores. June-Oct S. ripda Pursh 



5. Aehenes 2 mm long, the beak less than 1 mm long; pedicels 

 of the pistillate flowers equalling those of the staminate; 

 shallow water or margins of ponds and ditches. June-Sept. 

 S. grarninea Michx. 



127. Juncaginaceae Lindl. — Arrow-gra.ss Family 



1. Flowers numerous, greenish, in a long spike-like raceme; leaves all basal 



1. Triglochin 



1. Flowers few, white, in a loose raceme 2. Scheuchzeria 



1. Triglochin L. — Arrow-grass 

 1. Carpels usually 6, in fruit ellijjsoid, 3-6 mm long; .sandy oi- marly 

 swales, or in swamps or along ditches, not common; Cook, 



