Sagittaria. CXXXVIif. ALISMACEtE. 527 



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

 achenia collected into a globose head. — %■ acaulescent. Lvs. radical^ 

 generally sagittate. Fls. in verticils of 3, tlte sterile ones near the sum- 

 mit of the scape, fertile below them. 



1. S. SAGiTTiFOLiA. Arvowhead. 



Lvs. lanceolate, acute, sagittate, lobes lanceolate, acute. — A curious aquatic 

 plant, conspicuous with its large white flowers among the rushes and sedges of 

 sluggish waters, Can. and U. S. Root fleshy and farinaceous. Leaves 3 — 10' 

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

 smooth and entire. Scape 1 — 2f high, branching, obtu.sely 3-angled. Flowers 

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

 very delicate. Jul}^, Aug. — The leaves, «fec., are exceedingly variable, and Dr. 

 Torrey has appended the following, as varieties : 



/?. latifolia. Lvs. broad-ovate, rather obtuse, with straight, ovate, slightly 

 acuminate lobes. 



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

 acuminate lobes ; fls. mostly dioecious. 



6. gracilis. Ln:s. linear, with linear, very long, acute and spreading lobes. 



c. pubesceiis. Plant distinctly pubescent, in all its parts ; lvs, and their lobes 

 ovate. 



2. S, RiGiDA. 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, 5 — 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. HETEROPiiYLLA. Pursh. Vcirioxis-lcaved Arrowhead. 



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

 elliptical and sagittate, with lobes linear and divaricate; 5c«j!?<? simple, few-flow- 

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

 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 ses.sile, all with 

 roundish bracts at base. July. 



4. S. SIMPLEX, (acutifolia and graminifolia. Pursh.) Linear Sa^ittaria. 

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



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

 fls. § or (j^ 9, in whorls of 3, 4 or 5, .subterminal and terminal ; sta. in the bar- 

 ren flowers 12 — 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. OBTU.sA. Willd. Blunt Arrowhead. 



L/vs. broad-ovate, sagittate, rounded and mucronate at the apex, lobes ob- 

 long, obliquely acuminate, approximate and not spreading; /s. c^ 9; scope 

 simple, the sterile branched at the base; Israels 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. 



G. S. PUsii.LA. Nutt. Puny Arrowhead. 



Petioles (leaves 1) short, linear, obtu.se, summits only foliaceous ; scajye 

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

 7. — A diminutive species on muddy banks, N. Y. to Ga. Leaves rarely subu- 

 late, an inch or two long, less than a line wide. Scape 2 — 4' high. Plowers 

 4 — 7, the lowest one only fertile. Aug. 



7. S, NATANS. Michx. FUiatintr Sagiitaria. 



Lvs. floating, oval-lanreolato, obtu.'^c, 3-voincd. tnperin"' to the base, lower 

 45 



