68 NAIADACEAE 



Los Angeles River, Braunlon 571, to the San Joaqnin Valley and north to 

 Britisli Colniiiliia and east to the Atlantic coast. 



Var. greenei Graebner. Branches of the inflorescence more erect; achenes 

 rounded at summit. — Region of San Francisco Bay (Olema, Lake Merced) 

 south to Lower California and north to British Columbia. 



Refs. — SPAR(iANlUM EURYCAKPUM Engelm. in Gray, Man. 5th ed. 481 (1867). Var. GREENEI 

 Oraebnpr in Kngler, Pflzr. 4'°: 13 (1900). S. greenei Morong, Bull. Torr. Club, 15: 77 (1888), 

 type loc. Olema, Greene; .Tepson, Fl. W. Mid. Cal. 96 (1901). 5. californicum Greene, Bull. 

 Cal. Acad. T: 11 (1884), based on material from Calistoga, Sacramento and West Oakland. 



2. S. simplex Iluds. Stems erect, 1 to 3 feet high, or sometimes floating; 

 leaves 2 to lines broad, slightly carinate; inflorescence usually simple; stam- 

 inate heads 3 to 5, congested or confluent, but distant from the pistillate; 

 pistillate heads 2 to 6, the lowest peduncled, some supra-axillary, 8 or 9 lines 

 in diameter in fruit; nutlets narrow. 2 to 2y., lines long, 1 to V/^ lines thick on 

 the lower third, at ape.x gi'adually attenuate into the long style, long-pediceled, 

 often 2-celled. 



Sierra Nevada : Kaweah Meadows; Silver Lake; Placer Co. ; DonncrLake; 

 Goose Lake, Shasta Co. ; Modoc Co., Mrs. M. 77. Manmiuj. North to British 

 ('oluml)ia and east to New England and Newfoundland. 



Ref. — .'!par(:an-uim simplex Huds. Fl. Angl. 2d ed. 401 (1778). 



3. S. angustifolium I\lichx. Stems 1 to 4 feet high ; leaves exceedingly long 

 and narrow, 1 to '1\'-, lines broad, floating or erect: inflorescence simple; stam- 

 inate heads 2 to 6, sometimes blended but distant from the pistillate; pistil- 

 late heads sessile in the axils, often a little supra-axillary, rarely peduncled; 

 nutlets 21/; lines long, brownish, constricted at or above the middle, aliruptly 

 contracted at apex into the long .style or beak, pediceled. 



Lakelets arul slow streams: San Bernardino Mts. ace. Pai'ish. nortli to British 

 Columbia and east to Pennsylvania and Newfoundland. 



Refs.— Sparganu'M angustifolium Miclix. Fl. Bor. Am. 2: ISO (1803); Graebner in 

 Engler. Ptlzr. 4'": 16 (1900). S. Kimp^ex var. anrju.itifolmm Fngelni. in Gray, Man. 5th ed. 

 481 (1867); Parish, Erythoa. 6: 85 (1S9S). 



NAIADACEAE. Pundweed Famua-. 



Water iilants entirely submerged or with floating leaves. Leaves thread- 

 like or grass-like or some with In-oad floating blades, commonly sheathing at 

 ba.se or with .sheathing stipules. Flowers inconspicuous, naked or with a very 

 small calyx, commonly borne on a short spike or spadix. Ovaries 1 to 4. distinct, 

 free from the calyx if that be present, 1-celled, l-ovuled. ripening into nutlet- 

 like fruits. — Ten genera, the species of mostly wi<le disli-ibution. 



Bibliog. — Tnekerman. Edw.. Potamogetnn (Am. .T. Sei. 2d ser. vol. 6, pp. 224-30,— 1848 ; 

 vol. 7, pp. 347-()0, — 1849). Morong, T., Naiadaoeae of North .\merica (Mem. Torr. Club. 

 vol. 3, no. 2, — 1893). Dudley, Genus Phyllospadix (Wilder Quarter-century Book, pp. 403- 

 420, pl.9. 1-2, — 1893). Fryer, A., Potanu)gctons of the British Tsles (1898). Rendle, A. B, 

 Naiadaceae (Engler, Pflzr. tcil 4. abt. 12, — 1901). Campbell. V>. H., Morphological study of 

 Naias and Zannichellia (Proe. f'al. Acad. 3rd ser. Bot. vol. 1, pp. 1-70, pis. l-o, — 1897). Ascher- 

 son & Graebner, Potamogetonaceae (Engler, Ptlzr. teil 4, abt. 11, — 1907). 

 Flowers perfect, in spikes or clusters. 



Calyx of 4 distinct sepals 1 . Potamogetom. 



Calyx none 2. Ruppia. 



Flowers unisexual; calyx nfuie. 



Leaves entire. 



Pistils about 4. lioriic in a cnii-shaped involucre; fresh water jionds or streams 



3. Zannichellia. 



I 



