352 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



stem leaves lanceolate or oblong, clasping, 2 to 6 cm. long; petals white, 4 to 5 mm» 

 long; pods 4 to 6 cm. long, erect. 



10. Arabis glabra (L.) Bemh. East entrance and Belton, in thickets or on open 

 slopes. Alaska to Calif., Pa., and Que.; also in Eur. {Turritis glabra L.) — Stems 

 stout, hairy below; stem leaves lanceolate or ovate, 2 to 12 cm. long, glabrous, clasping; 

 petals white, 3 mm. long; pods erect, 4 to 10 cm. long. 



36. CAPPARIDACEAE. Caper Family. 

 1. CLEOME L. 



1. Cleome serrulata Pursh. Rocky Mountain beeplant. Along the railroad 

 near the east entrance; apparently introduced; abundant farther east on the plains. 

 Oreg. to Sask., N. Mex., and Ariz. {Peritoma serrulatum DC.) — Glabrous annual, 0.5 

 to 1 meter high; leaves palmate, stalked; leaflets 3, entire, oblanceolate; flowers pur- 

 ple; petals 4, about 1 cm. long; fruit a long slender stalked pod. 



The plant has a disagreeable odor; its flowers are showy. 



37. DROSERACEAE. Sundew Family. 



1. DROSERA L. 



Small perennials; leaves in a basal rosette, entire, stalked, covered \nth slender 

 gland-tipped hairs; flowers small, white, in a raceme; petals usually 5. — The sundews 

 are of great interest because of their carnivorous habits. The glands of the leaves 

 exude a sticky fluid, by which insects are entrapped, to be digested and used as food 

 by the plants. 



Leaves rounded, as broad as long 1. D. rotundifolia. 



Leaves oblanceolate, several times longer than broad 2. D. longifolia. 



1. Drosera rotundifolia L. Common sundew. Sphagnum bogs at Johns and Fish 

 lakes, and doubtless in similar places elsewhere. Alaska to Calif., N. J., and Lab.; 

 also in Eur. and Asia. — Leaves 6 to 10 mm. wide; stems 6 to 20 cm. high; petals 4 mm. 

 long; capsules 5 mm. long. 



The plants are not at all conspicuous and are half hidden in .the sphagnum. The 

 leaves and stems are more or less tinged with red. 



2. Drosera longifolia L. Narrowleaf sundew. Abundant in sphagnum bog 

 about Fish Lake. B. C. to Calif., Ont., and Newf.; also in Eur. and Asia. — Leaves 

 1.5 to 3 cm. long, 4 to 5 mm. wide; stems 5 to 20 cm. high; petals 5 mm. long. 



38. CRASSULACEAE. Stonecrop Family. 

 1. SEDUM L. Stonecrop. 



Perennial herbs with leafy stems; leaves narrow, fleshy, entire or toothed; flowers 

 in cymes; sepals 4 or 5; petals 4 or 5; stamens 8 or 10; fruit of 4 or 5 small pods. 



Petals dark purple 1. S. integrifolium. 



Petals bright yellow. . 



Leaves terete or nearly so, narrow at the base; plants without bulblets. 



2. S. stenopetalum. 



Leaves flattened, broadened at the base; flowers partly replaced by small plants or 



bulblets 3. S. douglasii. 



' 1. Sedum integrifolium (Raf.) A. Nels. Red orpine. Common above or near 

 timber line, on open rocky slopes. Alaska to Calif, and Colo. (Rhodiola integnfolia 

 Raf.) — Stems clustered, very stout, about 10 cm. high; leaves obovate or oblong, 

 1 to 1.5 cm. long, sometimes toothed; petals about 3 mm. long. 



A rather showy plant, especially in late summer, when the pods and leaves are 

 usually red or purple. 



