SACiiTTARiA. CXXXVIII. ALlSMACEiE. 527 



aggregated, and becoming, in fruit, as many compressed, margined 

 achenia collected into a globose liead. — % acaulesccnt. Lvs. radical^ 

 gciieraUij sagUtale. Fls. in verticils o/'3, t/i^ sterile ones near tlie sum- 

 mit of the scape^ fertile below them. 



1. S. SAGiTTiForJA. Arrowhcud. 



Lvs. lanceolate, <xcute,saj^'itlate, lobes lanceolate, acute. — A curious aquatic 

 plant, conspicuous wilh its larj^c white flowers amonf? the rushes and sedges of 

 sluggish waters, Can.^nd U. IS. Root fleshy and farinaceous. Leaves [^10' 

 long including the lobes which are nearly half this length, J — 4 or 5' wide, 

 smooth and entire. Scape I — 2{ high, branching, obtusely 3-angled. Flowers 

 generally in 3s, the upper ones barren. Petals 3, large, roundish, white and 

 very delicate. July, Aug. — The leaves, &c., are exceedingly variable, and Dr. 

 Torrey has appended the following, as varieties: 



p. faiifidia. Lvs. broad-ovate, rather obtuse, with straight, ovale, slightly 

 acuminate lobes. 



y. hastata. Lvs. oblong-lanceolate, acute, with spreading, lanceolate, long, 

 acuminate lobes; jls. mostly dioecious. 



(5. gracilis. Lvs. linear, with linear, very long, acute and spreading lobes. 



e. pubesccns. Plant distinctly pubescent, in all its parts ; lvs. and their lobes 

 ovate. 



2. S. RifiiDA. Pursh. Brittle-leaved Arrowhead. 



Lvs. narrow-lanceolate, carinate, rigid, very acute at both ends; scape 

 branching. — N. York. Growing in water even to the depth of 7 feet, accord- 

 ing to Dr. Beck. Leaves remarkably dissimilar to those of the foregoing spe- 

 cies, f) — 6' in length, one in width, thick and brittle, and on stout, rigid petioles, 

 prolonged according to the depth of the water. Flowers numerous and large, 

 with 3, white, rounded petals ; fertile ones on short peduncles. July. 



3. S. HETEROPHVLLA. Pursh. Various-leaved Arrmohead. 



Lvs. smooth, linear and lanceolate, acute at each end, rarely some of them 

 elliptical and sagittate, with lobes linear and divaricate; scape s\\n\)\e, few-flow- 

 ered, fertile flowers subsessile. — Muddy shores. Middle States. Leaves 2 — V 

 long, ^ as wide, on petioles rather longer than the scape which is seldom a foot 

 high. Flowers few, the three lower ones fertile and very nearly sessile, all with 

 roundish bracts at base. July. 



4. S. SIMPLEX, (acutifolia and graminifolia. Pursh.) Linear Sagitt<iria. 

 Lvs. erect, simple, linear and lance-linear, sheathing, hyaline and cellular 



at base, attenuated to a long, acute point; scape simple, longer than the leaves; 

 jls. § ox (^ (^ ,\n whorls of 3, 4 or 5, subterminal and terminal ; sta. in the bar- 

 ren flowers 1'2--15 ; bracts minute. — Muddy shores of ponds and rivers. Me. ! to 

 N. J., N. Y. ! W. to 111. A species almost "as variable as S. sagittifolia, to which 

 it is indeed appended by Hooker as another class of varieties. Leaves 4 — 7' 

 high, usually very narrow. Scape 5 — 8' high. Flowers 9 — 18, 8 — 9" diam. 

 Petals roundish, white. 



5. S. oBTusA. Willd. Blunt Arrowhead. 



Lvs. broad-ovate, sagittate, rounded and mucronate at the apex, lobes ob- 

 long, obliquely acuminate, approximate and not spreading; fis. j' 9; scape 

 simple, the sterile branched at the base; bracts ovate, acute.— Ditches, ponds 

 and marshes, Penn. to Va. W. to Ohio. Juice milky, exuding from the wounded 

 stem or leaves, and hardening into a pellucid gum.' Scape 1 — 2f high. Leaves 

 on long, radical, channeled petioles, lamina 3 — 5' by 2 — 3'. Flowers white, showy. 



6. S. PusiLLA. Nutt. Puni/ Arrowhead. 



Petioles (leaves'?) short, linear, obtuse, summits only foliaceous ; .^cape 

 ^simple, shorter than the leaves ; Jls. few, fertile one .solitary, deflexed ; sta. mostly 

 7~.- '^ diminutive species on muddy banks, N. Y. to Ga' Leaves rarely subu- 

 late, an ii,:^vor two long, less than a line wide. Scape 2 — V high. Flowers 

 4 — 7, the lowe>/ one only lertile. Aug. 



7. S. NAT> <is. Michx. Floating Sagittaria. 



Lvs. floating, oval-lanceolate, obtuse, 3-veined, tapering to the ba.se, lower 

 45 



