STANDLEY — FLORA OF GLACIER PARK. 279 



The plants are abundant in Fish Lake, in shallow or deep water, and some of the 

 stems must be several meters long. 



4. Potamogeton lucens L. Swiftcurrent Creek below Lake McDermott; pools at 

 St. Mary. Widely distributed in N. Amer. and Eur.^ — Plants reddish or brownish; 

 leaves 6 to 15 cm. long, 1 to 4 cm. wide, acute or obtuse, thin. 



6. Potamogeton richardsonii (A. Benn.) Rydb. Pond near east entrance, 

 Umhach. Alaska to Calif., Wyo., Del., and N. Y. — Leaves lanceolate, 5 to 10 cm. 

 long, acute or acuminate, 13 to 23-nerved, thin. 



6. Potamogeton pusillus L. Swiftcurrent Creek below Lake McDermott. Widely 

 distributed in N. Amer. and Eur. — Stems very slender; leaves 2 to 10 cm. long, 

 1 or 3-nerved. 



7. Potamogeton compressus L. Fish Lake. B. C. to Oreg., N. J., and N. B.; 

 also in Eur. — Stems slender, flattened; leaves thin, 5 to 20 cm. long, 3-nerved. 



8. Potamogeton interior Rydb. Swiftcurrent Creek below Lake McDermott, 

 Mont, to N. Mex. and Ont. — Stems slender, much branched, very leafy; leaves 

 3 to 15 cm. long, 1-nerved. 



9. Potamogeton pectinatus L. Ponds at east entrance, Umhach. Widely dis- 

 tributed in N. Amer. and Eur. — Stems much branched, very leafy; leaves 3 to 15 

 cm. long, very slender. 



11. SCHEUCHZERIACEAE. Scheuchzeria Family. 



1. SCHEUCHZERIA L. 



1. Scheuchzeria palustris L. In sphagnum bogs at Jolxns and Ksh lakes, and 

 probably elsewhere on the west slope. Alaska to Calif., N. J., and Lab.; also in 

 Eur. and Asia. — Glabrous perennial, 10 to 25 cm. high; leaves linear, 10 to 30 cm. 

 long; flowers white, the 6 segments about 3 mm. long; stamens 6; fruit of 3 to 6 

 spreading pods about 5 mm. long. 



12. ALISMACEAE. Waterplantain Family. 



Glabrous perennials with naked stems; leaves long-petioled, parallel-veined but 

 with numerous cross veins; flowers white, long-stalked, whorl ed, in racemes or 

 panicles; petals 3; fruit of numerous achenes. 



Leaves arrow-shaped, with sharp lobes at the base; achenes in several series on a 



convex receptacle 1. SAGITTARIA. 



Leaves oblong or ovate, never with lobes; achenes in a ring on a flat receptacle. 



2. ALISMA. 

 1. SAGITTARIA L. 



1. Sagittaria cuneata Sheld. Arrowhead. Low places on prairie at east entrance. 

 B. C. to Calif., N. Mex., N. Dak., Conn., and Me.— Plants 20 to 40 cm. high, with 

 spongy stems and petioles; leaves 6 to 15 cm. long, with 2 long basal lobes; flowers 

 in racemes, the lower ones pistillate, the upper ones staminate; petals about 1 cm. 

 long; fruit heads 1 to 1.5 cm. in diameter, the achenes with a short beak. 



2. ALISMA L. 



1. Alisma brevipes Greene. Waterplantain. Low places on prairie at east 

 entrance. B. C. to Calif., N. Mex., N. Dak., and N. S.— Plants 20 to 60 cm. high; 

 leaves 5 to 15 cm. long, acute or obtuse, rounded or subcordate at base; petals 5 to 

 6 mm. long; fruit heads 5 to 7 mm. broad. 



This may be the same as the Old W'orld A. plantago-aquatica L. The common 

 plant of eastern North America is a distinct species. 



